Which one of the following is a valid arithmetic expression? &X="y +5 OX=&y +5 X = y + 5 X = 8y + 5 Question 7 Not yet werd Marted out of 100 Flag question Which one of the following is used to redefine a data type? union pointer struct typedef Question 16 Not yet answered Marked out of 12.00 Flag question Which one of the following statement is true about the pointers in C++? Pointers are integer values used as addresses Pointers are special data types in C++ Pointers can't have NULL values Pointer are double values used as addresses