4. You are standing at point B. Point B is 21 feet from the center of the circular water storage tank and 19 feet from point A. AB is tangent to ⊙O at A. Find the radius of the tank. (Round answer to one decimal place)

4 You are standing at point B Point B is 21 feet from the center of the circular water storage tank and 19 feet from point A AB is tangent to O at A Find the ra class=