Need 15-16 year old Bf

Write an algebraic expression for the word expression the quotient of c and 8

Janet drove 300 miles in 4.5 hours. write an equation to find the rate at which she was traveling

On a string instrument, the length of a string varies inversely as the frequency of its vibrations. an 11-inch string has a frequency of 400 cylces per second. find the frequency of a 10-icnch string.