a-e please

Convert the following exercises that are given in decimal form into exercises and solutions in two's complement binary form (namely into the sum of two numbers in two's complement binary form; and the solution of this sum in two's complement binary form). In each case, specify how many digits are used in the 2's complement representation (i.e., what k is). (a) 31-19 (b) 35+25 (c) 32-57 (d) -20-12 (e) -17-13