Info: A jet pilot takes his aircraft in a vertical loop

Part 1: If the jet is moving at a speed of 1500 at the lowest point of the loop, determine the minimum radius of the circle so that the centripetal acceleration at the lowest point does not exceed 6.6 's.

I got the answer of this one to be 2.7 X 10^3

Part 2: Calculate the 68- pilot's effective weight (the force with which the seat pushes up on him) at the bottom of the circle, and at the top of the circle (assume the same speed).

I honestly don't even know where to start with this one. Can somebody help??

**1. The problem statement, all variables and given/known data**

**2. Relevant equations**

**3. The attempt at a solution**