The 'const' keyword creates a read-only variable. Once initialized, attempting to modify a const variable results in a compilation error (error: assignment of read-only variable). This is enforced at compile-time, not runtime.

char data type typically occupies 1 byte, which is the minimum. int is 4 bytes, float is 4 bytes, and double is 8 bytes on most systems.

The 'const' keyword declares a constant variable whose value cannot be modified after initialization. Attempting to modify it results in a compile-time error.

A 'long long int' is guaranteed to be at least 64 bits (8 bytes) by the C99 standard on all systems including 64-bit architectures.

string is not a fundamental data type in C. Fundamental types are int, float, double, char, and void. Strings are arrays of characters.

Both a and b are integers, so integer division is performed: 5/2 = 2 (remainder discarded).

Age is an integer value. Using 'int' is appropriate and memory-efficient. Floating-point types are unnecessary for this discrete value.

Signed char ranges from -128 to 127, while unsigned char ranges from 0 to 255. Both use 1 byte but interpret the bits differently.

The 'char' data type occupies 1 byte (8 bits) of memory on virtually all modern C systems, as per the C standard.

Implicit conversion truncates decimal part. int x = 3.7; results in x=3 with no error.