A popup clinic is doing virus testing with either spit tests or swabs. A spit test takes 10 minutes to administer while a  swab takes 15 minutes to administer. Since the spit test is more accurate, at least twice as many spit tests should be given as  swabs. However, at least 20  swabs must be administers. If the popup clinic operates for 8000 minutes, maximize the number of tests that can be administered.