Textbook Problem

Suppose that a vending machine company is considering selling some of its machines. Suppose further that the income from these particular machines is a continuous stream with an annual rate of flow at time t given by

$f\left(t\right)=12e^{-0.4\left(t+3\right)}$ in thousands of dollars per year. Find the present value and future value of the machines over the next 5 years if money is worth $10\%$ compounded continuously.