Please help this grade means a lot to me

In a school 2/3 of the students study a language of those who study a language 2/5 study french

Jermaine has t subway tokens. karen has 4 more subway tokens than jermaine. raul has 5 fewer subway tokens than jermaine. which expression represents the ratio of karen's tokens to raul's tokens

Out of 50 students surveyed, 16 have a dog. based on these results, predict how many of the 280 students in the school have a dog.