HELP PLS I BEG

The graph represents the gallons of water in a water tank with respect to the number of hours since it was completely filled

Consider a cube that has sides of length l. now consider putting the largest sphere you can inside this cube without any point on the sphere lying outside of the cube. the volume ratio -volume of the sphere/ volume of the cube is 1. 5.2 × 10−1 2. 3.8 × 10−1 3. 1.9 4. 2.5 × 10−1 5. 3.8

Use composition to determine if (x) or h(x) is the inverse of f(x) for the limited domain x2-1.