please answer the following question in C++ language

1. Answer each of the following questions about loops. In each question LABEL the three part of loop.

a) Write a while statement that will ask the user for integers until the user enters the sentinel value of -1. Declare all needed variables.

b) Write a for statement that will print out all of the multiples of 3 between 1 and 200. Declare any needed variables.

c) Write a do while loop that will ask the user for characters and end when the character is equal to 'e'. Declare any needed variables.