A "pick your own" strawberry farm charges each customer a $10 entry fee, plus $3 per pound of strawberries picked. Which of the following func- tions describes a customer’s total cost in dollars, c, as a function of the number of pounds of strawber- ries picked, p?

a. c(p) = 3p.
b. c(p) = 3p+10
c. c(p) = 10p+3
d. c(p) = 10p