There is one integer for which there does not exist another integer with the same absolute value, what is that integer?

I'm being volume of cylinder with 13 in. radius and 30 in height answer choices in pic

On traditional maps, earth is represented in a flat plane, or by euclidean geometry. however, a globe is a more accurate model that comes from elliptical geometry.how does a globe represent the fact that there are no parallel lines in elliptical geometry? the equator is not parallel to any other latitudinal lines. the north and south poles are never connected by a geodesic. the geodesics connecting the north and south poles never intersect. the geodesics connecting the north and south poles intersect at both of the poles.

Assume that y varies inversely with x. if y=1.6 when x=0.5 find x when y=3.2