On the 11th of March, 2011, an earthquake along the eastern shore of Japan caused a tsunami, which
then damaged a nuclear power plant. Several radioactive elements were released into the air and ocean.
Use an exponential decay formula to model how long some of these elements can be expected to persist
in the environment.
4. Cesium-137 has a decay constant of
0.0231 (a 30 year half-life). If 20
pounds of cesium-137 were released
into the Pacific Ocean by the tsunami,
how much will still be there ten years
later?
5. Strontium-90 has a decay constant of
0.0248 (a 28 year half-life). If 80
pounds of strontium-90 were
released into the Pacific Ocean by the
tsunami, how much will be left in 75
years?
6. When strontium-90 decays, it transforms into yttrium-90, which has a half-life of
only 64 hours, (0.007302 years). If the decay constant of yttrium-90 is -94.93,
what percentage of a one-pound sample will be left after one month ( of a
year)?

Answer:

10

Step-by-step explanation:

55³ + 66³ =

= (5 × 11)³ + (2 × 3 × 11)³

= 5³ × 11³ + 2³ × 3³ × 11³

= 11³(5³ + 2³ × 3³)

= 11³ × 341

= 11³ × 11 × 31

= 11^4 × 31

The factors are:

1, 11, 31, 11², 11³, 11^4, 11 × 31, 11² × 31, 11³ × 31, 11^4 × 31

The factors are:

1, 11, 31, 121, 341, 1331, 3751, 14641, 41261, 453871

Answer: 10

Answer: 3/4 hour

Step-by-step explanation: Add them all to get 3 3/4. subtract that from 4 1/2.

Answer:

10^8 represents 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10

Step-by-step explanation:

Because it is to the 8th power, this means it's multiplied by itself 8 times.

Answer: It represents b 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10

Step-by-step explanation:

Answer:

A.2

Step-by-step explanation:

x² = 16

take the square root of both sides

x = ±4

there are 2 solutions to the equations, those 2 solutions being 4 and -4

just to double check

4² = 4 × 4 = 16

-4² = -4 × -4 = 16

Answer:

8

Step-by-step explanation:

Answer

$15080

Step-by-step explanation:

ok so i havent done these in a while but basically.

First, we need to find out what the 6% is.

[tex]\frac{5}{100} \times \frac{11600}{1}[/tex]

5/100 because it's PERCENT, and well we need to put the 11600 out of 1.

Wich gives us

$580. THen, we multiply that by 6, (6 years). Which gives us

$3480. Now, we add that to the $11600. WHich gives us

$15,080.

Hope this helps!

Considering the area of a triangle, the region that has a population density less than 60 animals per square mile is:

C. c.

The area of a triangle of base b and height h is given by:
A = 0.5bh.

Item a:

We have that b = 40, h = 35, hence the area in miles squared is given by:

A = 0.5 x 40 x 35 = 700.

The density is the number of animals divided by the area, hence:

D = 42500/700 = 60.7.

Item b:

We have that b = 38, h = 25, hence the area in miles squared is given by:

A = 0.5 x 38 x 50 = 950.

Then, the density is:

D = 60800/950 = 64.

Item c:

We have that b = 42, h = 49, hence the area in miles squared is given by:

A = 0.5 x 42 x 49 = 1029.

Then, the density is:

D = 57300/1029 = 55.7.

Hence option C is correct.

More can be learned about the area of a triangle at https://brainly.com/question/21735282

Answer:

C.C-57,300

Step-by-step explanation:

From the dots the parabola’s are the same size just transitioned to different locations.

blue = y = x^2 + 3

Green = y = (x-4)^2

Orange = y = x^2 - 3

Purple = y = (x+4)^2

Answer: 48.8

Step-by-step explanation: The equation for the area of a circle is π*r², since the base of a cylinder is a circle we take the equation of a circle and multiply the height of the cynlinder by using the equation π*r²*h to get the volume of a cylinder. In this case our factors are

π= 3.14

r²= 6.76  

h=2.3

3.14*6.76*2.3=48.82072

rounded to the nearest tenth=48.8

Answer: the answer is 48.8

Answer:

The answer is 0.0026

Step-by-step explanation:

0.00032 x 5200000 = 1664

1664 divided by 640000 is 0.0026

Answer:

I don’t get it

Step-by-step explanation:

I think it is 5

its 54 also for some reason my comment keeps getting deleted for saying 54??

Answer:

-14 > -23

Step-by-step explanation:

-14 is greater than -23 since it is closer to 0 than -23.

hope this helps!! p.s. i really need brainliest :)

500 miles/ 25 = 20 x 0.50 = $10

He will save a total of $10

20-4 = $16

it will cost him $16 for the oil which is more than what he saves in gas so buying the oil is not worth it.

Answer:

Positive

Step-by-step explanation:

The graph goes up (puff puff positive)

Answer:

Step-by-step explanation: X = 4/3 or X= 1.3

3x + 1 = 5

3x = 5 - 1

3x = 4

X= 4/3 or X= 1.3

Answer:

yes

Step-by-step explanation:

A right triangle means that

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

[tex] {6}^{2} + {8}^{2} = {10}^{2} [/tex]

, which means that it follows the rules of the formula, making it a right triangle.

If this answer helped you I would appreciate it if you gave me brainliest :D

Answer:

C

Step-by-step explanation:

The poem itself, which is a funny description of sports.

Answer: C) the peom itself which is funny description of sports.

Step-by-step explanation: The reason this is the answer is because The poem they wrote towards the athletes and passion they have for sports.

[tex]3^{x-2} = \left(\dfrac 13 \right)^{\sqrt x}\\ \\\implies 3^{x -2} = \left(3^{-1} \right)^{\sqrt x} \\\\\implies 3^{x-2} = 3^{-\sqrt x}\\\\\implies x -2 = -\sqrt x\\\\\implies (x-2)^2 = \left(-\sqrt x \right)^2\\\\\implies x^2 -4x +4 = x\\\\\implies x^2 -5x +4 =0\\\\\implies x^2 -4x-x+4=0\\\\\implies x(x-4) -(x-4)=0\\\\\implies (x-1)(x-4)=0\\\\\implies x = 1~~~~~~;[x = 4 ~ \text{Does not satisfy the original equation}]\\\\\text{Hence, x =1 is the solution.}[/tex]

Answer:

45

Step-by-step explanation:

Since it given that her parent and grandmother attend a soccer game. Thus, we can see that there is no students.

Also given that:

Student tickets: $6

Non-Student tickets : $12

Parking : $9

Thus,

Non- Student tickets:$ 12 (Parents and grandmother are not students)

Parking: $9 ( Since they attend a soccer game they need somewhere to park)

Parents = 2 person (Mom and Dad)

Grandmother = 1 person

1 + 2 = 3

Now,

Since Non-student tickets = $12

3 * 12 +9

36 + 9

45

Hence, the family spend $45 to attend the game.

~lenvy~

Answer:

140.71

Step-by-step explanation:

WEEK 1- 100

WEEK 2- 105

WEEK 3-110.25

WEEK 4-115.7625

WEEK 5-121.550625

WEEK 6-127.62815625

WEEK 7-134.009564063

WEEK 8-140.710042266

By using an exponential equation, we will see that in the first 8 weeks she makes $954.90.

We know that the first week she makes $100, and for each week after that, she makes an extra 5%.

Then, the second week she makes:

W(2) = $100*(1 + 5%/100%) = $100*(1.05)

The third week she makes:

W(3) = $100*(1.05)*(1 + 5%/100%) = $100*(1.05)^2

We already can see the exponential pattern, for the N-th week, the salary will be:

W(N) = $100*(1.05)^(N - 1)

Then what she wins in the first 8 weeks is:

Now we just need to add these 8 values, we will see that the total money that she makes in these 8 weeks is:

M = $954.90

If you want to learn more about exponentials, you can read:

https://brainly.com/question/11464095

Answer:

11

Step-by-step explanation:

The formula for the area of a triangle is bh(1/2).

We can model an equation with:

22=4x(1/2)

multiply both sides by 2

44=4x

x=11

Answer:

I believe your answer is 15/7

Let's solve.

    [tex]\frac{30}{14} =\frac{15 * 2}{7*2} =\frac{15}{7}[/tex]

Hope that helps!

Answer:

750

Step-by-step explanation:

I multiplied the hours she worked by the amount of payment per hour.

Answer:

$750

Step-by-step explanation:

Since Lacey worked 40 hours with the condition that each hours, Lacey will be paid for $18.75, because they worked 40 hours, therefore:

[tex]\displaystyle \large{P = 18.75+18.75+18.75+...+18.75}[/tex]

From above, you add from first hour pay to 40th hour pay. However, that’d take quite a long time to evaluate:

[tex]\displaystyle \large{\sum_{H=1}^{40} 18.75 = 18.75 \cdot 40}[/tex]

Then evaluate 18.75 * 40 and therefore the solution is $750

For usage of formula:

P = RH for P = pay, H = hour and R = rate (pay per hour)

So if you use the formula, you’d still end up with P = 18.75*40 which is $750

Answer:

Step-by-step explanation:

D

Answer: 15

Based on this info they have a probability of 0.6 of winning a game.So for 15 games they should win 0.6*15  = 9 gamesSo prediction for whole season = 6+9 = 15 games.

Step-by-step explanation:

[tex]\qquad\qquad\huge\underline{{\sf Answer}}♨[/tex]

The required equation is :

[tex]\qquad \rm \dashrightarrow \:y =a \cos(bx) + k[/tex]

Now, let's find the required values :

period (p) = 6

[distance between any successive Crest or trough]

a = - 4 (flipped)

b = 2π/p = 2π/6 = π/3

k = -2

Distance of starting position from origin = k

Now, plug in the values ~

[tex]\qquad \rm  \dashrightarrow \: - 4 \cos( \frac{\pi}{3} x) - 2[/tex]

Find midpoint coordinates:

[tex]\rightarrow \sf (\dfrac{-1+3}{2} ), \ (\dfrac{7+(-1)}{2} )[/tex]

[tex]\hookrightarrow \sf (1, \ 3)[/tex]

Find the gradient of MN:

[tex]\dashrightarrow \sf \dfrac{-1-7}{3-(-1)}[/tex]

[tex]\dashrightarrow \sf -2[/tex]

slope of perpendicular bisector:

[tex]\rightarrow \sf \dfrac{1}{2}[/tex]

Equation:

[tex]\sf \rightarrow y = \dfrac{1}{2}x+\dfrac{5}{2}[/tex]

Answer:

[tex]y=\dfrac12x+\dfrac52[/tex]

Step-by-step explanation:

M = (-1, 7)

N = (3, -1)

[tex]\sf slope\:of\:MN=\dfrac{y_n-y_m}{x_n-x_m}= \dfrac{-1-7}{3-(-1)}=-2[/tex]

If two lines are perpendicular to each other, the product of their slopes will be -1.  Therefore, the slope (m) of the line perpendicular to MN is:

[tex]\sf \implies -2 \times m=-1[/tex]

[tex]\sf \implies m=\dfrac12[/tex]

If the line bisects the line MN, it will intersect it at the midpoint of MN:

[tex]\begin{aligned}\textsf{Midpoint of MN} & =\left(\dfrac{x_m+x_n}{2},\dfrac{y_m+y_n}{2}\right)\\ & =\left(\dfrac{-1+3}{2},\dfrac{7+(-1)}{2}\right)\\ & =(1,3)\end{aligned}[/tex]

Finally, use the point-slope form of the linear equation with the found slope and the midpoint of MN:

[tex]y-y_1=m(x-x_1)[/tex]

[tex]\implies y-3=\dfrac12(x-1)[/tex]

[tex]\implies y=\dfrac12x+\dfrac52[/tex]

The total dimension of the aquarium that will be cleaned by Steve will be 94 meters.

Your information isn't given. Therefore, an overview will be given. In this case, let's assume that the aquarium is rectangular. Let's assume the dimensions are 20m by 27m.

In this case, since she needs to clean the four walls of the aquarium, the total distance that will be cleaned will be:

= 2(Length + Width)

= 2(27 + 20)

= 2 × 47

= 94m

In conclusion, 94m will be cleaned.

Learn more about dimensions on:

https://brainly.com/question/19819849

Answer:

Both answer is C

Step-by-step explanation:

30:20

3:2

Thus, (24/3)×2

=16 inch

Use the sam method by making ratio first, then compare to the second figures and substitute the value in first figure

Answer:

7v and 4v are like terms, 9u is a term, and 5 is a constant.

Step-by-step explanation:

Like terms are terms that can be added together, such as numbers being multiplied by the same variable. A term is a number, a variable, or a number and a variable combined. A constant is a number that is not being multiplied or divided by a variable, but just a number on its own.