Dillon Computers purchases computers from a manufacturer for $500 per computer. The following graph setups depict product cost on the vertical axes and activity level on the horizontal axes:
Total product cost Product cost per computer

Number of computers sold Number of computers sold
Required
a. Draw a line that depicts the relationship between total product cost and the number of computers sold.
b. Draw a line that depicts the relationship between product cost per computer and the number of computers sold.