Nisha is looking out the window of her apartment building at a sculpture in a park across the street. The top of Nisha's window is 80 feet from the ground. The angle of depression from the top of Nisha's window to the bottom of the sculpture is 20°. How far away from the building is the sculpture? Round your answer to the nearest hundredth.

Answers

Answer 1

Answer:

219.80 feet

Step-by-step explanation:

Tan 20= 80/b

Tan 20= 0.363970234266

(0.363970234266)b=80

b= 219.80 feet

Answer 2

The distance between the sculpture and the bottom of the building is required.

The distance between the building and sculpture is 219.80 feet.

Trigonometry

[tex]\theta[/tex] = Angle of depression = Angle of elevation = [tex]20^{\circ}[/tex]

p = Height of building = 80 feet

b = Required length

From the trigonometric ratios we have

[tex]\tan\theta=\dfrac{p}{b}\\\Rightarrow b=\dfrac{p}{\tan\theta}\\\Rightarrow b=\dfrac{80}{\tan 20}\\\Rightarrow b=219.80\ \text{feet}[/tex]

Learn more about trigonometry:

https://brainly.com/question/23899312

Nisha Is Looking Out The Window Of Her Apartment Building At A Sculpture In A Park Across The Street.

Related Questions

A cylindrical grain silo, with a flat top, is 30 feet tall and has a radius of 12 feet. It is full to the top with shelled corn. If the density of shelled corn averages 45 pounds/cubic foot, what does the corn in the silo weigh to the nearest pound

Answers

Answer:

610805 pounds

Step-by-step explanation:

The volume of grain in the silo will be calculated as equal to the volume of the cylinder formed by the silo

Height of the silo [tex]l[/tex] = 30 ft

radius of the silo r = 12 ft

volume of a cylinder = [tex]\pi r^{2} l[/tex]

substituting, we have

V = 3.142 x [tex]12^{2}[/tex] x 30 = 13573.44 cubic feet

We know that density ρ = weight/volume

density of the grains in the silo = 45 pound/cubic feet

therefore,

weight of grains = density x volume

weight of grains = 45 x 13573.44 = 610804.8 ≅ 610805 pounds

Which of the following is a solution to 6x - 5y=4?
(2,7)
(-1, -2)
(-2, -1)
(2, -7)

Answers

Answer:

2,7

Step-by-step explanation:

Answer:

(-1,-2)

Step-by-step explanation:

(6 x -1) -(-2 x 5) = 4

-6 + 10 = 4

13.) Jessica earns 5 points for every assignment she completes, plus 15 points just for being in class on a given day. How many assignments does she need to complete to earn 65 points? First, write the equation that fits this model. Let z be the amount of assignments completed. *

Answers

Answer:

10

5z+15=65

Step-by-step explanation:

5z+15=65

5(10)+15=65

look at the image below plz helppppppppppppp

Answers

Answer:

150.

Step-by-step explanation

Which methods could you use to calculate the y-coordinate of the midpoint of vertical line segment with endpoints at (0,0) and (0,15)? Check all that apply

Answers

Answer:

Midpoint formula.

The midpoint formula is (x_1+x_2)/2 , (y_1+y_2)/2

Step-by-step explanation:

This is one method. A list wasn't provided.

let d equal the distance in meters and t equal the time in seconds. Which is a direct variation equation for this relationship

Answers

Answer:

d = s x t

Step-by-step explanation:

The formula for distance.

Suppose that the director of manufacturing at a clothing factory needs to determine whether a new machine is producing a particular type of cloth according to the manufacturer’s specifications, which indicate that the cloth should have a mean breaking strength of 70 pounds and a standard deviation of 3.5 pounds. A sample of 49 pieces reveals a sample mean of 69.1 pounds.

(a) State the null and alternative hypotheses.

(b) Is there evidence that the machine is not meeting the manufacturer’s specifications in terms of the average breaking strength? (Use a 0.05 level of significance.)

(c) Compute the p-value and interpret its meaning.

(d) What will your answer be in (b) if the standard deviation is 1.75 pounds?

(e) What will your answer be in (b) if the sample mean is 69 pounds?

Answers

Answer:

a.H0 : u1= u2 against Ha : u1≠ u2 This is a two sided test

b) There isn't enough evidence that the machine is not meeting the manufacturer’s specifications in terms of the average breaking strength.

c) the p- value is 0.0359*2= 0.0718. It is greater than the value of ∝ so there isn't enough evidence that the machine is not meeting the manufacturer’s specifications in terms of the average breaking strength.

d) There is enough evidence that the machine is not meeting the manufacturer’s specifications in terms of the average breaking strength.

e) There isn't enough evidence that the machine is not meeting the manufacturer’s specifications in terms of the average breaking strength.

Step-by-step explanation:

Formulate the null and alternative hypotheses as

a) H0 : u1= u2 against Ha : u1≠ u2 This is a two sided test

Here ∝= 0.005

For alpha by 2 for a two tailed test Z∝/2 = ± 1.96

Standard deviation = s= 3.5 pounds

n= 49

The test statistic used here is

Z = x- x`/ s/√n

Z= 69.1- 70 / 3.5 / √49

Z= -1.80

Since the calculated value of Z= -1.80 falls in the critical region we reject the null hypothesis.

b) There isn't enough evidence that the machine is not meeting the manufacturer’s specifications in terms of the average breaking strength.

c) the p- value is 0.0359*2= 0.0718. It is greater than the value of ∝ so there isn't enough evidence that the machine is not meeting the manufacturer’s specifications in terms of the average breaking strength.

d) If standard deviation is 1.75 pounds

The test statistic used here is

Z = x- x`/ s/√n

Z= 69.1- 70 / 1.75 / √49

Z= -3.6

This value does not fall in the critical region.

d) There is enough evidence that the machine is not meeting the manufacturer’s specifications in terms of the average breaking strength.

e) If the sample mean is 69 pounds

Z = x- x`/ s/√n

Z= 69.1- 69 / 3.5 / √49

Z= 0.2

This value falls in the critical region

e) There isn't enough evidence that the machine is not meeting the manufacturer’s specifications in terms of the average breaking strength.

If the Miller's spend $1200 on housing each month, then what is their total monthly budget?

Answers

Answer:

2400$

Step-by-step explanation:

Miller's Family spends 50% of their budget on housing and we know that they spent 1200$ this month, so 1200$*2 = 2400$.

Have a nice day! :-)

Find the value of x
9
7
X
9

Answers

Answer:

13.41

Step-by-step explanation:

You are so welcomed

The measure of each of the remaining angles in the right angle triangle is 45 degrees.

To find the measure of the remaining angles in the triangle, we can use the fact that the sum of the angles in any triangle is always 180 degrees. Since we know one angle is 90 degrees, we can find the measure of the other two angles by subtracting 90 from 180.

Let's call the remaining two angles A and B. Thus, we have:

Angle A + Angle B + 90 degrees = 180 degrees.

Rearranging the equation, we get:

Angle A + Angle B = 90 degrees.

Since the two sides of the triangle adjacent to the right angle are equal (given as 9 and 9), we can conclude that the remaining two angles are congruent (equal). Let's call the measure of each of these angles x.

Therefore, we have:

x + x = 90 degrees.

Simplifying, we get:

2x = 90 degrees.

Dividing both sides by 2, we find:

x = 45 degrees.

To know more about triangle here

https://brainly.com/question/8587906

#SPJ2

A line passes through the point (12,-4) and is perpendicular to the line with the equation y=6x +3

Answers

Answer:

y= -(1/6)x -2

Step-by-step explanation:

We know:

y= mx +b is the general equation of the line

Was given:

y= 6x +3, has the slope m=6

Find the equation of the line

y= -(1/6)x + b, perpendicular lines have their slope negative reciprocal m=-1/6

Find the y-intercept that is b

for point (x=12, y= -4) the equation of our line becomes

-4 = -(1/6)(12) + b, multiply a fraction and a number  (a/b)*c = ab/c

-4 = -12/6 +b, simplify the fraction

-4 = -2 + b , add 2 to both sides

-4+2 = -2+2 +b , solve for b

-2 = b

The equation of the line that passes through the point (12,-4) and is perpendicular to the line with the equation y=6x +3 is :

y= -(1/6)x -2

I need answering ASAP please and thank you

Answers

Answer:

one

Step-by-step explanation:

The red graph intersects the blue graph at one point

That is the number of solutions to the system

Answer:

one

Step-by-step explanation:

I had to do this question once. It was hard. I remember the answer. it is one. You have to trust me.

A health insurer has determined that the "reasonable and customary" fee for a certain medical procedure is $1200. They suspect that the average fee charged by one particular clinic for this procedure is higher than $1200.

Explain in context the conclusion of the test if H0 is rejected.

Answers

Answer:

For the null hypothesis to be rejected , then the conclusion of the test is that the absolute values of the z-statistic and/or the t-test statistic is greater than the critical value

Step-by-step explanation:

Here, we want to explain the conclusion of the test given that the null hypothesis is rejected.

Mathematically, the null hypothesis is as expressed as below;

H0: μ = 1,200

The alternative hypothesis H1 would be;

H1: μ > 1,200

Now, before we can reject or accept the null hypothesis, we will need a sample size and thus calculate the test statistics and the z statistics

For us to reject the null hypothesis, one of two things, or two things must have occurred.

The absolute value of the z statistic |z| or the test statistic |t| must be greater than the critical value.

If this happens, then we can make a rejection of the null hypothesis

Cuánto es 324 por 171

Answers

Answer:

la respuesta es 55,404

I hope this helped

A clock rotated from 12 to 6 this is

Answers

Answer:

one half

Step-by-step explanation:

Because the rotation from 12 to 6 is one-half of a complete rotation, it seems reasonable to assume that the hour hand is moving continuously and has therefore moved one-half of the distance between the 2 and the 3. source- ck12.org

THE PRICE OF AN ITEM FROM $10 TO $17. WHAT WAS THE PERCENT INCREASE IN THE PRICE OF THE ITEM?

Answers

Answer:

70%

Step-by-step explanation:

The method to find out percentage increase is by subtracting the original price from the increased price and making it into a fractional form with the denominator as 10 (out of 100%). So it results to this.

(original price - increased price) / 10

(17 - 10) / 10 = 7/10

7/10 can be converted from its fractional form to 70% i.e.its percentage.

Hope this helps and please mark as the brainliest.

Find the value of x.

Answers

x=2.86

Step-by-step explanation:

[tex] {a}^{2} + {b}^{2} = {c}^{2} [/tex]

[tex] {24}^{2} + {32}^{2} = 40[/tex]

[tex]c = 40[/tex]

[tex]6x + 6 + 9x - 9 = 40[/tex]

[tex](6x + 9x) + (6 - 9) = 40[/tex]

[tex]15x - 3 = 40[/tex]

[tex]15x = 43[/tex]

[tex]x = 2.866[/tex]

[tex]23.16 + 16.74 = 39.9[/tex]

the

[tex]6(2.86) + 6 = 23.16[/tex]

[tex]9(2.86) - 9 = 16.74[/tex]

2 1/2 cases of soda to split between 5 families

Answers

The fraction that each person gets is 1/2.

How to compute the fraction?

It should be noted that 2 1/2 cases of soda to split between 5 families.

In their case, the fraction that each person will get will be:

= Total / Number of people

= 2 1/2 ÷ 5

= 2.5/5

= 0.5 or 1/2.

Learn more about fractions on:

brainly.com/question/17220365

#SPJ1

2 1/2 cases of soda to split between 5 families. What fraction will each person get?

Two years ago the population of a town was 40000. The population of the town at present has reached 44100. Calculate the population growth rate of the city.​

Answers

Answer:

5% annual population growth rate

Step-by-step explanation:

Let the percent the population grows by be [tex]X\%[/tex]. The total population, [tex]f(x)[/tex], after [tex]t[/tex] years can be modeled by the function:

[tex]f(x)=40,000\cdot (\frac{X}{100}+1)^t[/tex]

Why?

Let's take a look at a simple example. If we said a number [tex]n[/tex] grew by 10%, we could represent the number after it grew by multiplying [tex]n[/tex] by [tex]1.10[/tex]. This is because growing by 10% is equivalent to taking [tex]100\%+10\%=110\%[/tex] of that number and we convert a percentage to a decimal by dividing by 100.

Therefore, if the population grew [tex]X\%[/tex], we would divide it by 100 to convert it to a decimal, then add 1 (100%) and raise to the power of [tex]t[/tex] (number of years) to multiply by the initial population of 40,000 to get the total population after [tex]t[/tex] years.

Since the population of the town after two years is 44,100, substitute [tex]f(x)=44,100[/tex] and [tex]t=2[/tex] into [tex]f(x)=40,000\cdot (\frac{X}{100}+1)^t[/tex]:

[tex]44,100=40,000\cdot (\frac{X}{100}+1)^2,\\\\(\frac{X}{100}+1)^2=\frac{44,100}{40,000},\\\\(\frac{X}{100}+1)^2=1.1025,\\\\(\frac{X}{100}+1)^2=\pm \sqrt{1.1025},\\\\\begin{cases}\frac{X}{100}+1=1.05,\frac{X}{100}=0.05, X=\boxed{5\%},\\*\text{negative case is extraneous since X must be positive}\end{cases}[/tex]

Therefore, the city has an annual population growth rate of 5%.

PLEASE HELP!!! TIMED QUESTION!!! FIRST CORRECT ANSWER WILL BE BRAINLIEST!!!

The bar graph shows the number or each item sold at a bake sale. Which statement about the graph is true?​

Answers

The answer is 2. You can see from the graph that 10 cookies were sold. If you take 1% of 10 and add it to 10, you get 11, which is exactly how many cupcakes were sold
Number 1 is correct.
Let me know if you need the working out. Hope it helps :)

There are nickles and quarters worth $2.20 in total. If there are 28 coins, how many nickels are there?

Answers

Answer:

There are 24 nickels

Step-by-step explanation:

Let x represent the number of nickels

Let y represent the number of quarters
—————————————————————

Value Value
Type Number of of
of of each all
Coin Coin Coin Coin
—————————————————————
Nickels | x | $0.05 | $0.05x
Quarters | y | $0.25 | $0.25y
—————————————————————
Totals 28 ——— $2.20
•••••••••••••••••••••••••••••••••••••••••••••••••

The first equation comes from the “Number of coins” column.

(Number of nickels) + (Number of quarters) = (total number of coins)

Equation: x + y = 28
—————————————————————
The second equation comes from the “value of all coins” column.

(Value of all nickels) + (Value of all quarters) = (Total value of all coins)

0.05x + 0.25y = 2.20

Remove the decimals by multiplying each term by 100:

5x + 25y = 220
—————————————————————
So we have the system of equations:

{x + y = 28
{5x + 25y = 202

Solve by substitution. Solve the first equation for y:

x + y = 28
y = 28 - x

Substitute (28 - x) for y in 5x + 25y = 220

5x + 25 (28 - x) = 220
5x + 700 - 25x = 220
-20x + 700 = 220
-20x = -480
x = 24

The number of nickels is 24.
————————————————————
Substitute in y = 28 - x
y = 28 - (24)
y = 4

The number of quarters is 4.
————————————————————
Checking:

24 nickels is $1.20 and 4 quarters is $1.00
That’s 28 coins.
Indeed $1.20 + $1.00 = $2.20
————————————————————

Find the volume of the following figure round your answer to the nearest tenth if necessary and use pi

Answers

Answer:

Volume = 1152 x pi km^3

Step-by-step explanation:

Volume = 1/3 x pi x r^2 x h

Volume = 1/3 x pi x 12^2 x 24

Volume = 1152 x pi

solve the system with elimination 4x+3y=1 -3x-6y=3

Answers

Answer:

x = 1, y = -1

Step-by-step explanation:

If we have the two equations:

[tex]4x+3y=1[/tex] and [tex]-3x - 6y = 3[/tex], we can look at which variable will be easiest to eliminate.

[tex]y[/tex] looks like it might be easy to get rid of, we just have to multiply [tex]4x+3y=1[/tex]  by 2 and y is gone (as -6y + 6y = 0).

So let's multiply the equation [tex]4x+3y=1[/tex]  by 2.

[tex]2(4x + 3y = 1)\\8x + 6y = 2[/tex]

Now we can add these equations

[tex]8x + 6y = 2\\-3x-6y=3\\[/tex]

------------------------

[tex]5x = 5[/tex]

Dividing both sides by 5, we get [tex]x = 1[/tex].

Now we can substitute x into an equation to find y.

[tex]4(1) + 3y = 1\\4 + 3y = 1\\3y = -3\\y = -1[/tex]

Hope this helped!

Oak street and elm street run parallel to each other. When main street intersects them, it forms exterior 8, measuring 60. What is the measure of 1?

Answers

Answer:

0 is the answer measure 1

A potato chip manufacturer produces bags of potato chips that are supposed to have a net weight of 326 grams. Because the chips vary in size, it is difficult to fill the bags to the exact weight desired. However, the bags pass inspection so long as the standard deviation of their weights is no more than 3 grams. A quality control inspector wished to test the claim that one batch of bags has a standard deviation of more than 3 grams, and thus does not pass inspection. If a sample of 21 bags of potato chips is taken and the standard deviation is found to be 4.1 grams, does this evidence, at the 0.025 level of significance, support the claim that the bags should fail inspection

Answers

When we take data at work, we always do it over a period of time. To me, just one sample set does not show enough data to come to that conclusion. Also it is one batch of bags. I think you would need to have an average of data from different batches & samples to prove your data is accurate and support your claim.

Find f(-2) given f(x) = –x^3 – 3x^2 +8

Answers

Answer:

Option A, 4

Step-by-step explanation:

f(-2) = -(-2)³-3×(-2)²+8

= 8-12+8

= 16-12

= 4

Sarah had a balance of $155 in her bank account at the start of the week. She withdrew $65.50 on Monday, $23.25 on Wednesday, and $26.45 on Thursday. On Friday she deposited $165.30. Write an expression that represents Sarah's spending.

Answers

Answer:

155 + 165.3 - 65.5 - 23.25 - 26.45

Step-by-step explanation:

She had $155 dollars in the starting = +155

She withdrew $65.5 = -65.5

She withdrew another $23.25 = -23.25

She withdrew another $26.45 = -26.45

The deposited $165.3 = +165.3

The expression looks like:

155 + 165.3 - 65.5 - 23.25 - 26.45

We could simplify the expression:

155 + 165.3 - 65.5 - 23.25 - 26.45

=> 320.3 - 88.75 - 26.45

=> 320.3 -115.2

=> 205.1

At the end of the week, she had a total of $205.10.

Please find the answer

Answers

Answer:

0.3 is the right answer.

Step-by-step explanation:

hope this helps

In the data set shown below, what is the value of the quartiles?

{4.3, 4.5, 4.7, 5, 5.5, 5.7, 5.9, 6, 6.1}
A. Q1 = 4.6; Q2 = 5.5; Q3 = 5.95
B. Q1 = 4.7; Q2 = 5.5; Q3 = 6
C. Q1 = 4.7; Q2 = 5.5; Q3 = 5.9
D. Q1 = 4.6; Q2 = 5.5; Q3 = 5.92

Answers

Answer:

A. Q1 = 4.6; Q2 = 5.5; Q3 = 5.95

Step-by-step explanation:

{4.3, 4.5, 4.7, 5, 5.5, 5.7, 5.9, 6, 6.1}

First find the median or the 2nd quartile

There are 9 data points so the middle is the 5th

4.3, 4.5, 4.7, 5,     5.5,     5.7, 5.9, 6, 6.1}

Q2 = 5.5

Now looking at the data on the left, we need to find the middle, which is Q1 or the first quartile

4.3, 4.5     , 4.7, 5,

It is between 4.5 and 4.7 so we average

(4.5+4.7)/2 = 9.2/2 = 4.6

Q1 is 4.6

We do the same for the data on the right, which is the third quartile or Q3

5.7, 5.9,  6, 6.1

(5.9+6)/2 = 11.9/2 = 5.95

Q3 = 5.95

Answer: IT'S A !!

Step-by-step explanation:

NEED ASAP! Given: AB = 12 AC = 6 Prove: C is the midpoint of AB. A line has points A, C, B. Proof: We are given that AB = 12 and AC = 6. Applying the segment addition property, we get AC + CB = AB. Applying the substitution property, we get 6 + CB = 12. The subtraction property can be used to find CB = 6. The symmetric property shows that 6 = AC. Since CB = 6 and 6 = AC, AC = CB by the property. So, AC ≅ CB by the definition of congruent segments. Finally, C is the midpoint of AB because it divides AB into two congruent segments. Answer choices: Congruence Symmetric Reflexive Transitive

Answers

Answer:

It’s symmetric property

Answer:

Symmetry

Step-by-step explanation:

The guy above me

In an interview for a secretary position at the dealer, a typist claims a tying speed of 45 words per minute. On
On the basis of 70 trials, she demonstrated an average speed of 43 words per minute with a standard deviation of 15 words per minute.
Test at 5% significance level on the typist’s claim.

Answers

Using the hypothesis test for one sample mean, There is NO SIGNIFICANT EVIDENCE to support the typist's claim

[tex]H_{0} = 45\\H_{1} < 45\\\\[/tex]

The test statistic :

T = (x - μ) ÷ (s/√(n))

T = (43 - 45) ÷ (15/√70)

T = - 2 ÷ 1.7928429

T = -1.12

At α = 0.05

Pvalue :

Degree of freedom, df = 70 - 1 = 69

Pvalue = 0.1333

Decision region :

Reject [tex]H_{0}[/tex] if Pvalue < α

0.1333 > 0.05

Since Pvalue > α We fail to reject the Null

Learn more on hypothesis testing: https://brainly.com/question/20262540

Other Questions
La presa de Hidroituango tiene una altura de 225 m., alberga 20 millones de m^3 de volumen y una cresta de 550 metros de longitud, suponiendo que es un cuadriltero con la base inferior de 200 m de longitud, determine las dimensiones y rea superficial de la presa . You have two solutions, both with a concentration of 0.1M. Solution A contains a weak acid with a pKa of 5. ThepH of solution A is 3. Solution B contains a weak acid with a pKa of 9. The pH of solution B is: 1. How can you find the decimal forms of 3/12 and 2/9 . What is the name of the property illustrated in the equation below?5+(3x+0)=5+3x There is a zombie outbreak in a city that infects 10 people right away. Each of the 10 zombies are able to infect 2 people every minute. How many people are infected in 8 minutes? NoGrowth Corporation currently pays a dividend of per quarter, and it will continue to pay this dividend forever. What is the price per share of NoGrowth stock if the firm's equity cost of capital is ? A pair of adjacent coils has a mutual inductance of 1.5 H. If the current in one coil changes from 0 to 20 A in 0.5 s, what is the change of flux linkage with the other coil? Flaming BBQ restaurant makes a dipping sauce with 9 mL of hot sauce for every 6 ounces of barbecue sauce. Which of the following mixtures will taste the same as flaming BBQ's dipping sauce?Choose 3 answers:A. 6 mL of hot sauce mixed with 20 oz of barbecue sauceB. 3 mL of hot sauce mixed with 2 oz of barbecue sauceC. 45 mL of hot sauce mixed with 30 oz of barbecue sauceD. 24 mL of hot sauce mixed with 18 oz of barbecue sauceE. 12 mL of hot sauce mixed with 8 oz of barbecue saucepls help me ;-; Two hikers are miles apart and walking toward each other. They meet in hours. Find the rate of each hiker if one hiker walks mph faster than the other. What else would need to be congruent to show that AABC = APQR by SSS?GiverAC =PRBC = QRA AC = PQB. AB = PQC. ZAZPD. ABBA a car gets 27 miles per gallon in the city and 35 miles per gallon on the highway. what range of miles can the car travel on 3 gallons of gas log, (x + y)=log, y, log, x .Solve for question D only Bowlby argued that infants perform behaviors which increase the probability that adults will care for them. This idea was based on the principle that ducklings will also increase the probability that they will survive if they perform certain behaviors. What was the specific behavior that we discussed in class that ducklings perform which may increase their probability of survival Find the measure of each side indicated. Round to the nearest tenth.A) 19.8C) 24.9B) 27.2D) 25.3 A lorry can safely carry 90 boxes each of mass 75kg . how many boxes each of mass 27kg .can it carry safely The midpoint of line segment AB is (1,2). if the coordinates of A are (1,0) what are the coordinates of B Compute the flux H F of F(x,y) = hxy, x yi across the boundary of the square given by 1 x 1, 1 y 1. In the first paragraph, which line states a reason why humans are at fault for the lionfish problem?O What was once just an attractive aquarium fish has recently become one of the biggest menaces in the AtlanticO The lionfish was accidentally introduced into the Atlantic Ocean in the 1990s.O Because it has no natural predators, it has adapted quickly to its new homeThe lionfish now threatens to destroy native fish populations in the Atlantic, Caribbean, and Gulf of Mexico. -7m-3(-5m-4)=-61My answer is always decimals??? Its weirdplease help why was domesticating and confining animals so important to the food supply of early civilization