Christina knows that her monthly cell phone bill depends on the amount of data that she uses. what can you learn by looking at the graph? a) if christina uses 50 mb of data, she will not be charged a cell phone bill for the month. b) christina is charged $20 for every 1,000 mb of data she uses. c) christina is charged $100 for every 2 mb of data she uses. d) if christina uses 80 mb of data, then her monthly bill will be $1,500.

I believe it’s
b if I’m wrong please list me know:)

  the correct answer is : binding price ceilings encourage the formation of a black market

The answer is    (d) 7/2======we have    we also  have an integral      notice how function f splits up at x = 0. there's a left piece and a right pieceso we'll need to do the same thing with our integral: split it at x = 0we use a property of integrals that allows us to split up and sum:     notice that for the piecewise function f, the function has the equationf(x) = x when x  ≤ 0. so for the integral  , f(x) = x so it changes into      for the piecewise function f, the function has the equationf(x) = x+1  when x  > 0. for the integral  , we have    therefore, back to our splitted integral: