Pointers in C are often passed to a function as arguments. This allows data items within the calling portion of the program to be accessed by the function, altered within the function, and then returned to the calling portion of the program in altered form. We call this use of pointers in functions as passing arguments by reference (or by address or by location), in contrast to passing arguments by value. When an argument is passed by value, the data item is copied to the function. Thus, any alteration made to the data item within the function is not carried...