Gertrude is deciding which cell phone plan is the best deal for her to buy. Super Cell charges a monthly
fee of $10 and also charges $0.15 per call. She makes a note that the equation is M = $0.15C + $10.
where M is the monthly charge, in dollars, and C is the number of calls placed. Global Cellular has a plan
with no monthly fee but charges $0.25 per call. She makes a note that the equation is M = $0.25C, where
M is the monthly charge, in dollars, and C is the number of calls placed. Both companies offer unlimited
text messages.
Type your answer to c - which cell phone plan is a better buy for Gertrude? Be specific.