1-Using C++ predefined functions, write each of the following as C++ expression. 1- + 2b+4a c + 2 ................................................................................................................................. ................................................................................................................................. 2- + | + 2| ................................................................................................................................. ................................................................................................................................. 3- = + a ................................................................................................................................. ................................................................................................................................. 4- = + 74 2 ................................................................................................................................. ................................................................................................................................. 2-Write the definition of a void function called Threetimesfun that takes as input an integer number and output 3 times the value of the integer number. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. 3-Write the definition of a void function called initialize with two reference parameters of type int and double. The function sets the values of the int and double variables to 0. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. Computer Programming (2) Exercises ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. 4-Write the definition of a function called PrintNaturallNumbers with two parameters (start and end) of type int. The function prints all the numbers from start to end. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. 5- Write a program that prompts the user to enter two numbers (n1 and n2) then swap them. Your program must have the following function: a. Swap: This function takes the reference parameters of n1 and n2 and swap their values.