Can y’all help me :3

Part a: sam rented a boat at $225 for 2 days. if he rents the same boat for 5 days, he has to pay a total rent of $480. write an equation in the standard form to represent the total rent (y) that sam has to pay for renting the boat for x days. (4 points)

True or false: the graph of y=f(bx) is a horizontal compression of the graph y=f(x) if b< 1

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