Question

preciso de ajuda por favor

Answer 1

a) 7+6+8 = 21
b) -8-6-3 = -17
c) 5-6-7+1 = -7
d) -28+7+12-1-6 = -16
e) -21-7-6+15-2+10 = -11
f) 10+8-9+12-6+5 = 20