Hola necesito ayuda con geometría

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

Simplify (1/2)4th power a. (1/16) b.(1/8) c.(1/4)

Barney & noblet customers can choose to purchase a membership for $25 per year members receive 10% off all store purchases 1. how much would a member pay per year if he bought $50 worth of items each year? 2. write a slope-intercept equation that expresses how much a member pays per year using x to represent his purchases per year 3. how much would a member have to spend per year to pay off his membership fee?