5/9 ÷ 5/7 plz a short answer doing it now o i hate math plz so bad at it

If benito is selecting samples of five values from the table, which row will result in the greatest mean? row 1 row 2 row 3 row 4

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.

Astick 2 m long is placed vertically at point b. the top of the stick is in line with the top of a tree as seen from point a, which is 3 m from the stick and 30 m from the tree. how tall is the tree?