A cell phone plan costs $39 a month. The plan includes 2 gigabytes (GB) of free data and charges $15 per gigabyte for any additional data used. The monthly charges are a function of
the number of gigabytes of data used, given by
C (x) = (x)
39, if 0 ⩽ x ⩽ 2
39 + 15 (x − 2), if x > 2
(a) Find C(0.5), C(2), and C(4) .
(b) What do your answers in part (a) represent?
(c) Is C(x) continuous at x = 2?