In a C++ program, program, two slash marks (//) indicate: a) The end of a statement b) The beginning of a comment c) The end of the program d) The beginning of a block of code e) None of the above Which one of the following would be an illegal variable name a) day Of Week b) -employee-num c) 3dGraph d) June1997 e) itemsorderedforthemonth Character constants in C++ are always enclosed in: a) [brackets] b) " double quotation marks" c) 'single quotation marks' d) {braces} e) (parentheses)