What is 0 times anything? ? (i'm asking this so you can answer it and get points, you're welcome)

Given that ot =5, xt=12, and ox= 13 is xy tangent to circle o at t? explain.

For each proportion find the unknown number x 1/5/8=×/15

Aball is dropped from a height of 10m above the ground. it bounce to 90% of its previous height on each bounce. what is the approximate height that the ball bounce to the fourth bounce?