2 . a) 1125 – ( 374 + 1125) + (-65 +374) = 1125 - 1499+309 = -374 + 309 = -65
b) -23 . 63 + 23 . 21 – 58 . 23 = -1449 + 483 - 1334 = -996 + 483 = -513
c) -2003 + (-21+75 + 2003) = -2003 + 2057 = 54
d) 942 – 2567 + 2563 – 1942 = -1625 + 2563 – 1942 = 938 - 1942 = -1004