1/5 is what percent f the whole quantity

The vet charges $45 for an office visit and $10 for each vaccination your dog needs. write an eaquation

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.

60 musicians applied for a job at a music school. 14 of the musicians play both guitar and drums, 28 play drums, 18 play the guitar. what is the probability that the applicant who gets the job plays drums or guitar?