Please help I am very confused on what to do.

What is the inverse of the function f(x) = 2x + 1?

Last year, a state university received 3,560 applications from boys. of those applications, 35 percent were from boys who lived in other states. part a)how many applications did the university receive from boys who lived in other states? part b)applications to the university from boys represented 40percent of all applications. how many applications did the university receive in all? i don't how to do part b so me and plz tell how you got your answer

For what type of equity loan are you lent a lump sum, which is to be paid within a certain period of time? a. a line of credit b. equity c. a second mortgage d. an amortization