If u want to find the depth of a submarine during a dive, would it be more reasonable to use an equation with the rate in feet per minute or per hour

Meg constructed triangle poq and then used a compass and straightedge to accurately construct line segment os, as shown in the figure below, which could be the measures of angles pos and angle poq?

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

Me because i don't understand how to do it.: )