If u role a standard number cube what probability of riling a 2

I’ve been trying all day to figure this puzzle out. i need the work for it aswell. it is a factoring polynomials tarsia. the image is below.

David leaves his house to go to school. he walks 200 meters west and 300 meters north. how far is david from his original starting point?

If 7x=9y, y/z = 7/5 , then x/z = (a) 2/7 (b) 7/9 (c) 9/5 (d) 9/7 (e) 5/9