The following pairs of numbers A and B are in ones complement representation with the left most bit indicating the sign. Calculate (A + B), (A B), (- A + B), and ( A B) for each pair using 8-bit ones complement binary arithmetic. Check your results by decimal arithmetic. Explain any unusual results if there are any. (a) 10000000, 01111111 (c) 1101011, 0101010 (b) 11101010, 101111 (d) 1010101, 1010