NEED HELP LOL XD OH MY GODDD

On a piece of paper graph f(x)=5•(0.4)^x

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

Which expression is rational? 6. , square root two, square root 14, square root 49