Answer:
2450 J
Explanation:
Given that,
A 50Kg girl jumps off a 5-meter-high diving board.
We need to find the kinetic energy of the girl before she hits the water. At this point the kinetic energy becomes equal to the potential energy such that,

So, her kinetic energy right before she hits the water is equal to 2450 J.
Laws that implemented the consumers' right to be informed forbid misleading advertising.
Answer is C.
Just because the book is moving doesn't tell you anything about the forces on it, or even whether there ARE any.
Just look at Newton's first law of motion, and this time, let's try and THINK about it too. It says something to the effect that any object continues in constant, uniform MOTION ..... UNLESS acted on by an external force.