How u solve it is you follow you signs and you go step by step and you will have your answer if that makes sense
Using an exponential function, it is found that the mass of the radioactive sample at the beginning of the 13th day of the experiment was of 169.1 mg.
<h3>What is an exponential function?</h3>
A decaying exponential function is modeled by:

In which:
- A(0) is the initial value.
- r is the decay rate, as a decimal.
At the beginning of the first day of the experiment the mass of the substance was 500 grams and mass was decreasing by 8% per day, hence A(0) = 500, r = 0.08, and the equation is given by:



At the 13th day, the mass is given by:

More can be learned about exponential functions at brainly.com/question/25537936
Answer:
He needs 37.8 meters altogether.
Step-by-step explanation:
Because each plank is 2.7 meters, we can just multiply 14 by 2.7 to get 37.8 meters.
It is the second answer choice
Divide both sides by the coefficient 6 to get p <span>≥ −24/6 = -4
p </span><span>≥ −4</span>