This Question is confusing the heck out of me can someone help me with it.

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

Present age of man is 45 years, 5 years back his age was 4 times age of his son what is present age of his son?

Cody ran nine miles on his first day of training. the next day he ran 1/8 that distance. how far did he run the second day?