Is this right?? If not please tell me the answers

What are the coordinates of the midpoint of ab? ,1/2) /2,-1) ,-3/2) /2,-2)

The number of fish in a lake can be modeled by the exponential regression equation y=14.08 x 2.08^x where x represents the year

The radius of the sphere is 10 units .what is the approximate volume of the sphere use π=3.14