(Please read and answer 1,2,3 in C++)

1) Write a program that prompts the user to enter an uppercase letter and finds its corresponding lower case letter.

Sample run:

This program prompts the user to enter an upper case letter and displays the corresponding lowercase letter.

Enter Y to continue and N to quit: Y

Enter the upper case letter: W
The corresponding lowercase letter is: w

Enter Y to continue and N to quit: Y

Enter the upper case letter: E
The corresponding lowercase letter is: e

Enter Y to continue and N to quit: N
END OF PROGRAM

2) Write a program that outputs three letters to a file. This program writes three letters i, B, and k to the file named "letters.txt".

Sample run : Done

3) Write a program that inputs three letters from a file. This program inputs three letters from the file named "letters.txt" and displays the three letters.

Sample run:

The letters are i, B, and k.

Done