A college print shop leases an industrial Xerox photo copier for $1,500 per month plus 1.5 for every page. Additional printing costs are estimated at 2 per page, which covers toner, paper, labour, and all other incurred costs. If copies are made for students at 10 each, determine the following: a. How does net income change with every 100 copies sold? b. What is the monthly net income if, on average, the shop makes 25,000 copies for students each month?