That is more of a History of English question.

Explanation:
At the top of the tree, the velocity of the pebble is purely horizontal so we can calculate it as


Answer:
False
Explanation:
Gravity force is constant.
There some places on Earth that gravity has a variation, but in general, it is the same everywhere.
If you analyze the equation for the weight, which is the action of the gravity to mass, you'll see that W=mg, where m is the mass and g, is gravity.
If you increase the mass, what you are increasing is weight and not gravity.
Explanation:
Below is an attachment containing the solution.