Write a python program to solve the following problems:

a) Sum: Prompt the user for a positive Integer n. Calculate the sum of the first n positive Integers.

b) Average: Prompt the user for a number of values to be entered, then prompt for each value. Finally calculate their average.

c) Average of Squares: Calculate the average of the squares of n positive, odd Integers starting at 1.

(The user should provide the value of n.)