ASAP
Element X decays radioactively with a half life of 7 minutes. If there are 120 grams of Element X, how long, to the nearest tenth of a minute, would it take the element to decay to 2 grams?

it will take 41.3 minutes

Step-by-step explanation:

We would apply the formula,

y = ab^t

Where

a represents the initial amount of bacteria.

t represents the half life.

From the information given

a = 120

t = 7 minutes

Since after 7 minutes, the amount of bacteria reduces by 0.5, then

y = 0.5 × 120 = 60

Therefore

60 = 120 × b^7

Dividing through by 120, it becomes

0.5 = b^7

Raising both sides of the equation by 1/7, it becomes

0.5^(1/7) = b^7/7

b = 0.9057

The equation becomes

y = 120(0.9057)^t

For the element to decay to 2 grams, then

2 = 120(0.9057)^t

2/120 = (0.9057)^t

0.0167 = (0.9057)^t

Taking log of both sides, it becomes

Log 0.0167 = tlog0.9057

- 1.777 = - 0.043t

t = - 1.777/- 0.043

t = 41.3 minutes

the answer is b i just did that

step-by-step explanation:

answer:

it is general formula that is used to write value to its excet position

a11 a12 a13

a21 a22 a23

it is the example of order 2 by 3 matrix in this

a11 means value occur in 1 st row 1st column

a12 means value occurs in 1st row 2nd column

a13 means value occur in 1st row and 3rd column

a21 means value occurs in 2nd row and 1st column

a22 means value occurs in 2nd row and in 2nd column

a23 means value occurs in 2nd row and in 3rd column