Please help! 10 Points!

1: How do you know if a mapping diagram shows a function?

2: How do you know if a table of values shows a function?

David must install fencing around a lot that is shaped like a right angle.the side of lot that runs east-west is 200 ft long.the side of the lot runs north-south is 125 ft long.calculate how many feet of fencing he will need to surround the entire lot.

The graph of f(x), shown below, resembles the graph of g(x) = x2, but it has been changed somewhat. which of the following could be the equation of f(x)?

The volume of a sphere is increased by 6%. calculate the corresponding percentage increased in it area.