The Clear-Bell Cell phone company has a plan that costs
customers $29.99 for a monthly service fee plus 3¢ per minute used.

a. Write a linear equation to model this situation.
b. Identify the slope and the y-intercept. Interpret the slope and y-intercept in the context of this problem.
c. If Polly talks for 136 minutes, how much would her cell phone bill be (excluding taxes)?