The cell phone plan from company c costs $10 per month, plus $15 per gigabyte for data used. the plan from company d costs $80 per month, with unlimited data. rule c gives the monthly cost, in dollars, of using g gigabytes of data on company cs plan. rule d gives the monthly cost, in dollars, of using g gigabytes of data on company ds plan. using function notation, write rule c and rule d. c(g) = 10 d(g) = write a sentence describing the meaning of the statement c(2) = 40.