This is not an exponential function. If you were to graph this out, you would see a parabola forming. Or at the very least, a parabolic-like curve forms. An exponential curve only increases or only decreases for the entire domain. However, in this case, we have an increasing portion, and then it decreases.
This is an exponential function. Each time x increases by 1, y is multiplied by 4. The equation that models these points is y = 4^x. Note how the function is strictly increasing and there are no decreasing portions mixed in.
The mean is the average, add all of the values and divide the result by the number of values. The MAD is the mean absolute deviation. You find it by taking the distance between the values and the mean. You then add them together and divide it by the mean. I really hope this helps you!
