need help with these three

1.5 Add, subtract, and multiply in binary 1.6 Subtract in binary, Place a 1 over each column from which it was necessary to borrow 1.7 Add the following numbers in binary using 2's complement to represent negative (a) 1111 and 1010 (b) 110110 and 11101 (c) 100100 and 10110 (a) 11110100 1000111 (b) 1110110 111101 (c) 10110010 111101 numbers Use a word length of 6 bits (including sign) and indicate if an overflow occurs. (a) 21 +11 (b) (14) (-32) (c) (-25) 18 Repeat (a).(c). (d), and (e) using 1's complement to represent negative numbers