21. Finance A beauty salon schedules appointments for haircuts for 30 minutes and
for special services, such as tinting or curling, for 1 hour. Each haircut costs $20. and
special services cost $45. The beauty salon wants to schedule no more than 4 special
services each day per beautician. Find the number of each type of appointment that
produces the maximum income per beautician in a workday of 8 hours at most.