Throw it vertically on the air, and catch the ball again maybe...
There is a rat, cat, and dog. You want to across all of them to the other side of the river.
The ship can only take one animal only.
If you left the cat with the rat, the cat will kill the rat
If you left the cat with the dog, the dog will kill the cat
So how do you bring them to the other side of the river safety?