4. Write a recursive C++ function that returns the number of 1's in the binary representation of N. Use this fact. The number of 1's in N is equal to the number of 1's in N/2, except when N is odd where you need to add value 1 Tum in a complete program including your test cases. Must test with multiple test cases!!! (15 points) 5. Show that the insertion sort we discussed has the worst-case performance of O(N2). (10 points) Drove he