A manufacturer produces two models of toy airplanes. It takes the manufacturer 6 minutes to assemble model A and 9 minutes to package it. It takes the
manufacturer 7 minutes to assemble model B and 5 minutes to package it. In a given week, the total available time for assembling is 840 minutes, and the total
available time for packaging is 900 minutes. Let x be the number of model A units produced. Let y be the number of model B units produced. Shade the region
corresponding to all values of x and y that satisfy these requirements.
