Parisa’s cell phone plan has a monthly fee of $95, which includes unlimited free text messages and phone calls and 5GB of data. Each extra gigabyte of data, or part thereof, costs $14.
a. Find the cost of a month in which Parisa used 6.2GB of data.
b. If x represents the number of gigabytes used, express the monthly charge c(x) of this plan as a piecewise function.