Suppose Richard has an after- tax income of $500 per week and must spend it all on food or clothing. If food is $5 per pound and clothing is $10 per piece, draw his budget line, where the amount of food is measured along the vertical axis and the amount of clothing is measured along the horizontal axis.

a. What is the budget line if Richard's weekly in- come increases to $600?

b. What is his budget line if his income is $500, but the price of food increases to $10 per pound?

c. What is his budget line if his income is $500, but the price of clothing increases to $20 per piece?