If necessary, create a new project named Introductory21 Project and save it in the Cpp8\Chap14 folder. Also create a new source file named Introductory21.cpp. If you are using Microsoft Visual C++, copy the Introductory21.txt file from the Cpp8\Chap14 folder to the Cpp8\Chap14\Introductory21 Project folder. Use a text editor to open the Introductory21.txt file, which contains 10 uppercase letters of the alphabet. Close the Introductory21.txt file. Create a program that counts the number of letters stored in the file. The program should display the number of letters on the computer screen. Save and then run the program.