The amount (A) in milligrams of aspirin in a person's bloodstream can be modeled by A = (391t^2 + 0.112)/(0.218t^4 + 0.991t^2 + 1) where t is the time in hours after one dose is taken.

a. A second dose is taken one hour after the first dose. Write an equation to model the amount of second dose in the bloodstream.

b. Write a model for the total amount of aspirin in the bloodstream after the second dose is taken. (The second dose plus the first one)

  about 5.6 days

step-by-step explanation:

we can fill the given information into the decay equation and solve for the value of t at which half the sample remains.

the half-life is about 5.6 days.

option: d is correct

step-by-step explanation:

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so:

$3,200 x 7.25% = $3,200 x .0725 = $232 interest monthly

$232 monthly x 12 annual = $2, 784

step-by-step explanation: