Question

In order to gain popularity amongst high school students, Starbucks is creating a special winter promotion on Starbucks. The function below represents the cost of a Starbucks as a function of time (measured in days after December 4th).
Piece wise function
c(t)=
5; 0<= t <= 5
5 + 1; 5 < t <= 15
25; 15 < t <= 27
a) What would be the best dates to buy a Starbucks?
b) calculate c(9) - c(5)

Answer 1

costs nothing for the first 6 days,t = 0 through 5 ?

c(t) = 5+1 ???
no t, does not makes ense

Answer 2

5 + t

Answer 3

(a) clearly during the first 5 days, when the cost is just 5.

c(9) = 5+9 = 14
c(5) = 5
so, ...