Chapter 13.3, Problem 48E

(a)

To determine

To calculate: The function $f\left(t\right)=p\left(t\right)q\left(t\right)$ which gives the rate of spending in millions of dollars per year from the years 2020 to 2040, on residential propane.

(b)

To determine

To calculate: The function $F\left(t\right)$ which gives the total amount of money spent in millions of dollars in the year $t$ on residential propane.