Question 1 :
A short integer is at least 16 bits wide and a long integer is at least 32 bits wide.
The basic C compiler is 16 bit compiler, below are the size of it's data types The size of short int is 2 bytes wide(16 bits). The size of long int is 4 bytes wide(32 bits).
Question 2 :
If scanf() is used to store a value in a char variable then along with the value a carriage return(\r) also gets stored it.
No, the carriage return tells the compiler to read the input from the buffer after ENTER key is pressed.
Question 3 :
The modulus operator cannot be used with a long double.
fmod(x,y) - Calculates x modulo y, the remainder of x/y. This function is the same as the modulus operator. But fmod() performs floating point or long double divisions.
Question 4 :
A char variable can store either an ASCII character or a Unicode character.
Yes, we can store either an ASCII character or a Unicode character in a char variable.