Suppose Bob is only willing to buy a bike seat if he can also buy a bike seat cover to go with it, i.e. Bob needs an equal number of bike seats and bike seat covers. Bob has $100 in income.

a. Suppose bike seat covers cost $1 and bike seats cost $19. How many of each will Bob buy? Discuss and illustrate graphically.

b. Suppose the price of bike seats increases to $49. How will Bob react to the price change? Discuss and illustrate on the same graph as in part a.