read and solve please

A school is preparing a trip for 400 students. The company who is providin the transportation has 10 buses of 50 seats each and 8 buses of 40 sears, but only has 9 trivers available. The rental cost for a large bus is $800 and $600 for the small bus. Calculate how many buses of each type should be used for the trip for the least possible cost. Let L= Number of Large Busses to Use Let S= Number of Small Busses to Use Minimize Cost =$ A L+$ A S Subject to: L+S L S A Limit on Number of Drivers .... One Driver per Bus A Limit on Number of Large Busses A Limit on Number of Small Busses A L+AS A Need to Transport a Minimum Number of Students