a photocopy machine company produces three types of laser printers- the print jet, the print desk, and the print pro. the sales of which earn profits of $60, $90, and $73. the print jet requires 2.9 hours of assembly time and 1.4 hours of testing time. the print desk requires 3.7 hours of assembly time and 2.1 hours of testing time. the print pro requires 3 hours of assembly time and 1.7 hours of testing time. the company wants to ensure that print desk constitutes at least 15% of the total production and print jet and print desk together constitutes at least 40% of the total production. there are 3,600 hours of assembly time and 2,000 hours of testing time available for the month. what combination of printers should be produced to maximize profits?