a) (56-27)-(56-37+12)
First, let's simplify the expression inside the parentheses:
(56-27) = 29
(56-37+12) = 31
Now, we can substitute these values back into the original expression:
29 - 31
Finally, we can subtract:
29 - 31 = -2

b) 232-(581+132)
First, let's simplify the expression inside the parentheses:
(581+132) = 713
Now, we can substitute this value back into the original expression:
232 - 713
Finally, we can subtract:
232 - 713 = -481

c) (35-17)-(25-7+22)
First, let's simplify the expression inside the parentheses:
(35-17) = 18
(25-7+22) = 40
Now, we can substitute these values back into the original expression:
18 - 40
Finally, we can subtract:
18 - 40 = -22

d) (72-1956)-(-1956+28)
First, let's simplify the expression inside the parentheses:
(-1956+28) = -1928
Now, we can substitute this value back into the original expression:
(72-1956) - (-1928)
Finally, we can subtract:
-1884 - (-1928) = -1884 + 1928 = 44