A sample of 500 g of radioactive​ lead-210 decays to​ polonium-210 according to the function A(t)=500e^-0.032t ​, where t is time in years. Find the amount of radioactive lead remaining after ​(a) ​3yr, ​(b) 8​yr, ​(c) 10 yr. ​(d) Find the​ half-life.

Answer:

100 degrees

Step-by-step explanation:

Answer:

Domain = x - values

Range = y - values

Step-by-step explanation:

main points I'll use as examples for the rest on graph are: (-3,4) (1,2) and (1,6)

Domain: simple numbers here are {-3,1} dont repeat the same x value twice!

Range: {2,4,6}

Make sure values are in numerical order.

Find the rest by these three points! (Which are on graph)

Hope this helps, have a good day :)

Answer:

try 2

Step-by-step explanation:

because it an X-value and it on the graph

Answer:

They will bisect eachother

Step-by-step explanation:

meaning they will cross in the middle

Answer:

24

Step-by-step explanation:

20+4

simple

x-4=20

x=20+4

x=24

mark me as brainliest

Answer:

24 sweets

Step-by-step explanation:

Remaining sweets = 20

x - 4 = 20

Add 4 to both sides.

x = 20 +4

x = 24

Answer:

                                                   inequality sign to opposite one

b ≤ - 19/14  and the answer choices B, C and D are all correct as are less than -19/14

A. 140 is the only one incorrect

Answer:

8

Step-by-step explanation:

more details

2(10)-3(4)

20-12

8

Answer: 180 gallons

Step-by-step explanation:

If you take 8 times 6 you get 48, now take 132 plus 48 and you get 180.(hope this helped):)

Answer:

(5,2)

Step-by-step explanation:

The 90° clockwise rule (for around the origin) is: [tex](x,y)\rightarrow(y,-x)[/tex]

Apply the rule to point A:

[tex]\left \{ {(-2,5)\rightarrow(5,2)} \atop {(x,y)\rightarrow(y,-x)}} \right.[/tex]

A' should be (5,2).

Answer:

Step-by-step explanation:

The general rule for rotation of an object 90 degrees is (x, y) to (-y, x)

so for point A(-2,5), A' will be (5,2)

to find the new

X=xcos(θ)+ysin(θ)

X=-2(cos90)+5sin90             ( cos90=0, sin 90=1)

to find the new

Y=−xsin(θ)+ycos(θ)

Y=-(-2)sin90+5cos90

I think the length is 17.75cm and the width is 12.75 cm

I'm not entirely sure whether it's the smallest possible length but it works on the calculator

17.75*2+12.75*2=61

Answer:

True

Step-by-step explanation:

integers like 5 or 4 can be put over one to be a fraction.

For example: 5/1 or 4/1

Answer:true

Step-by-step explanation:

they can

eg 1/1, 7/1

Answer:

32

Step-by-step explanation:

2^5

This is 2 multiplied by itself 5 times

2*2*2*2*2

32

Answer:

1.2 = 12/10 = 6/5

2.25 = 225/100 = 9/4

3.5 = 35/10 = 7/2

4.06 = 406/100 = 203/50

Answer:

Era

Step-by-step explanation:

Century, Decade and Millennium have something in common and that which they have in common is that they are all measurement of time.

The keyword measurement implies that they are units of time just like seconds, minutes, hours, etc.

Century -> 100 years

Decade -> 10 years

Millennium -> 1000 years

However, era is used to describe events in history;

Take for instance; the era of the first generation of computer;

So, from the list of given options; Era best answers the question

An era describes a time period marked by a change that begins a new period.

An era :

Examples of eras include:

All the eras mentioned above were distinct in how people behaved so in conclusion we can say that an era is a time period that begins a new period of development.

Find out more at https://brainly.com/question/20315058.

Answer:

The correct option is;

12.3 + 0i

Step-by-step explanation:

The form a + b·i is the complex number form where the variables a and b are real numbers and i is the square root of -1, √(-1) that is i² = -1. As the answer to  √(-1), cannot be found among the real numbers, i, is known as an imaginary number.

As such  a given complex number of the form a + b·i, has a real, part or component, a, and an imaginary part, b.

The number 12.3, is a real number, therefore, representing the number in a complex number format, the imaginary part, b, would be zero, as follows;

12.3 + 0·i

1 - 580squaredcm

2 - 540

Answer:

6.5×10'3=6,500.

5.5×10'5=550,000

1.1×10'3=1,100

so as u can see the second number is greater

by 548,900

Answer:C

Step-by-step explanation: 5.5 is 500 times better than 1.1 I did the math.

5.5 x 10^5 = 550,000

1.1 x 10^3 = 1,100

500 times greater

Answer:

(3)(x + 4)(x-2)

Step-by-step explanation:

3x^2 + 6x – 24

3(x^2 + 2x - 8)

(3)(x + 4)(x-2)

Answer:

3(x - 2)(x + 4).

Step-by-step explanation:

3x^2 + 6x – 24

= 3(x^2 + 2x - 8)

= 3(x - 2)(x + 4).

Answer:

D.

24x + 18y ≤ 225

x + y ≥ 10

Step-by-step explanation:

"He wants to frame no fewer than 10"

x + y ≥ 10

"and he can spend a maximum of $225. Large frames cost $24, and medium frames cost $18."

24x + 18y ≤ 225

Answer:

D.

24x + 18y ≤ 225

x + y ≥ 10

Answer: D.

24x + 18y ≤ 225

x + y ≥ 10

Step-by-step explanation: "He wants to frame no fewer than 10"

x + y ≥ 10

"and he can spend a maximum of $225. Large frames cost $24, and medium frames cost $18."

24x + 18y ≤ 225

Answer: D.

24x + 18y ≤ 225

x + y ≥ 10

This question is incomplete because the options are missing; here is the complete question:

Kareem wants to find the number of hours the average sixth-grader at his school practices an instrument each week. Which is the best way Kareem can get a representative sample?

A. He can randomly survey 50 boys in the school.

B. He can survey 30 students in the school band.

C. He can randomly survey 50 6th graders in the school.

D. He can survey 20 friends from his neighborhood.

The correct answer is C. He can randomly survey 50 6th graders in the school.

Explanation:

A representative sample is a portion of a population that shows the characteristics of all the population. In this context, for a sample to be representative it needs to include only individuals of the population that is studied. Also, ideally, individuals should be selected randomly as this guarantees the sample is not influenced by the researcher. According to this, option C is the best as this is the only one that focuses on the target population (6th graders) and the sample is random, which contributes to the sample being objective and representing the behavior of 6th-graders.

Answer:

He can randomly survey 50 sixth-graders in the school.

Step-by-step explanation:

Answer:

Step-by-step explanation:

The graph of function f(x)+2 is moved 2 units up compared to the graph of f(x).

It means the x-coordinate is the same and the y-coordinate of f(x)+2 is increased by adding 2 to y-coordinate of f(x).

-8 + 2 = -6

3√3 is not equivalent to 9³/₄

3√3 is equivalent to   [tex]9^\frac34[/tex]

step-by-step:

[tex]9^\frac34=(3^2)^\frac34=3^{2\cdot\frac34}=3^{\frac32}=3^{1+\frac12}=3^1\cdot3^\frac12=3\cdot\sqrt3=3\sqrt3[/tex]

The simplest form of the number [tex]9^\frac{3}{4}[/tex]   is  [tex]3 \ \sqrt[]{3}[/tex].

It is given that the  [tex]9^\frac{3}{4}[/tex]

It is required to find the simplest value of [tex]9^\frac{3}{4}[/tex]

It is defined as the number if we multiply the number by itself we get the original number it is a non-negative number.

We have:

= [tex]9^\frac{3}{4}[/tex]

We can write the above number as below:

[tex]= (3^2)^\frac{3}{4}[/tex]

By the property of powers:

[tex]\rm (x^a)^b= x^a^\times ^b[/tex] , we get:

[tex]3^2^\times^\frac{3}{4} \\\\\\3^\frac{3}{2} \\\\\sqrt{3^3} \\\\\sqrt{3}\times \sqrt{3}\times\sqrt{3}\\\\3\sqrt{3}[/tex]

Thus, the simplest form of the number [tex]9^\frac{3}{4}[/tex]   is  [tex]3 \ \sqrt[]{3}[/tex].

Learn more about the square root of the numbers here:

https://brainly.com/question/1527773

Answer: A.

Step-by-step explanation:

1/4 is not in fact a natural number, it's a rational number, a ratio.

Answer:

1. u = 2, v = -1.5

2. y = -7, x = -3

Step-by-step explanation:

1) For the following simultaneous equation, we have;

5·u + 2·v = 7....................(1)

2·u - 2·v = 7......................(2)

Adding equation (1) to equation (2), gives;

5·u + 2·v + 2·u - 2·v = 14

5·u + 2·u + 2·v- 2·v   = 14

7·u = 14

u = 14/7 = 2u = 2

u = 2

From equation (1), we have;

5·u + 2·v = 7 substituting u = 2 gives;

5×2 + 2·v = 7

2·v = 7  - 5×2 = 7 - 10 = -3

v = -3/2 = -1.5

v = -1.5

2.

3·x - 4·y = 19....................(1)

4·x - 5·y = 23.......................(2)

Multiplying  equation (1) by 4 and equation (2) by 3 gives;

For equation (1)

4 × (3·x - 4·y) = 4 ×19

12·x - 16·y = 76...........................(3)

For equation (2)

3 × (4·x - 5·y) = 3 × 23

12·x - 15·y = 69...........................(4)

Subtracting equation (3) from equation (4) gives;

12·x - 15·y - (12·x - 16·y) = 69 - 76 = -7

12·x - 15·y - 12·x + 16·y = 69 - 76 = -7

12·x - 12·x - 15·y + 16·y = -7

y = -7

Substituting the value of y = -7 in equation (1), we have;

3·x - 4·y = 19 = 3·x - 4×(-7) = 19

3·x - 4×(-7) = 19

3·x + 28 = 19

3·x = 19- 28  = -9

x = -9/3 = -3

x = -3.

Answer: plot a point at (-8, -5)

The y coordinate flips from positive to negative, or vice versa, when we reflect over the horizontal x axis. The x coordinate stays the same.

The rule can be written as [tex](x,y) \to (x,-y)[/tex]

Answer:

10.5 m²

Step-by-step explanation:

Given:

∆ with 2 side lengths, 4.7m, 6.1m, and an included angle, 47°.

Required:

Area of the triangle

SOLUTION:

Area of such triangle that has 2 known sides and an included angle between them is given as ½*a*b*sin(θ).

Where,

a = 4.7 m

b = 6.1 m

θ = 47°

Area = ½*4.7*6.1*sin(47)

Area = 10.5 m² (to the nearest tenth)

Answer:

0.249

Step-by-step explanation:

tan(theta) = opposite / adjacent (according to the SOH CAH TOA rule), which effectively means y/x in this case.

So -0.242 / -.970 ≈ 0.249

Other explanation:

On a unit circle,

y = sin(θ)

and

x = cos(θ).

And since, tan = sin/cos, tan(θ) = y/x. You y and x are given, so calculating tan is a matter of dividing them.

Answer:

£10.1

Step-by-step explanation:

Highest exchange rate=1.3401

Lowest exchange rate=1.3199

The money Khan would have received more if he exchanged currencies at the highest rate compared to the lowest rate=500*(1.3401-1.3199)=£10.1

Step-by-step explanation:

the ratio of boys and girls is equal to 4:5

let the number of boys be x

and the number of girls be y

so form 1st statement

x:y=4:5

now 2nd statements

x:y-100=6:7

Therefore solving equations 1 and 2

x=1200

y=1500

Answer:

4x

Step-by-step explanation:

8x-2y=5

8x=2y+5

8x-5=2y

4x-5/2=y

The slope of the parallel line would be 4x because the slope doesn't change. Hope this helps.

Answer:

The answer is the first one

Step-by-step explanation:

The cost of an adult ticket is $15

The price of an adult ticket is 1/2 the price of a student ticket plus $8

x is the cost of a student ticket, so

1/2(x) + $8 = $15