you want to estimate the radius of the towns circular water tank. you stand at point c, about 6 feet from the circular tank. the distance from you to a point of tangency on the tank is about 10 feet. estimate the radius of the tank

Answer 1

Did you mean spherical water tank?
or
water tank is a cylinder with a circular base?

"about 6 feet from the circular tank" ---- 6 feet to the closest point of the tank?
or

" the distance from you to a point of tangency on the tank is about 10 feet"
- if it is a sherical water tank, then there are two tangents, one horizontal and one which is slanted.

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