Question:What is the use of a ‘\0’ character? 

It is referred to as a terminating null character, and is used primarily to show the end of a string value.

Question:How do you determine the length of a string value that was stored in a variable? 

To get the length of a string value, use the function strlen(). For example, if you have a variable named FullName, you can get the length of the stored string value by using this statement: I = strlen(FullName); the variable I will now have the character length of the string value.

Question:Which function in C can be used to append a string to another string? 

The strcat function. It takes two parameters, the source string and the string value to be appended to the source string.