Programming Concepts

TRUE. Although for most languages it is a convention rather than part of the language syntax.

TRUE. In some programming languages there are constants that are predefined and can't be changed at any time. In most languages you can identify your own constants that have a value that is fixed by you.

FALSE. Any type of data can be made a constant. How that is done is language dependent.

TRUE. Although the same rules apply as for variable names, for example no spaces or special characters.

TRUE. Although the usual data matching rules will apply - you wouldn't be able to multiply an integer variable by a constant containing characters.