1- Answer each of the following: a) A program module in C is called a(n) b) A function is invoked with a(n) A variable that is known only within the function in c) which it's defined is called a(n). d) The pass the value of an expression back to the calling function. statement in a called function is used to is used in a function header to indicate e) Keyword that a function does not return a value or to indicate that a function contains no parameters. f) A function that calls itself either directly or indirectly is a(n) function.