Can someone help me with this pls

When you are making a circle graph by hand, how do you convert a number for a part into its corresponding angle measure in the circle graph? when you are making a circle graph by hand, what should you do if one of your angle measures is greater than 180°?

How to find the exponential function y=ca^x, with points (1,2) and (2,1)

Felix wrote several equations and determined that only one of the equations has no solution. which of these equations has no solution?