A specific radioactive substance follows a continuous exponential decay model. It has a half-life of minutes. At the start of the experiment, 82.6g is present. a. Let t be the time (in hours) since the start of the experiment, and let y be the amount of the substance at time t. Write a formula relating y to t. Use exact expressions to fill in the missing parts of the formula.
Do not use approximations.

y= ___e^

b. How much will be present in 18 hours?

Step-by-step explanation:

Half life of a substance is the time the substance to reduce to half of its original. Half life is expressed as where is the decay constant.

Given half life of the substance to be 12 hours, we can get the decay constant

a) Given the initial mass of the substance y₀ = 82.6g, we can find the amount of substance remaining after time t using the formula;

Substituting  y₀ = 82.6g and λ = 0.05775 into the formula given;

Hence the formula relating y to t is expressed as

b) To calculate the amount that will be present after 18 hours, we will substitute t = 18 into the expression in (a) as shown;

Hence about 29.2099958 g will be present after 18 hours

move it to the other side

step-by-step explanation: