Explicação passo-a-passo:
a) +10+0-9+2-12+15=
+10 -9+2-12+15=
+1 +2-12+15=
+3-12+15=
-9+15=
+6
b) 27+16 +4-30 +2=
43 +4-30+2=
47 -30+2=
17 +2=
19
c) 2-⁵ ÷ 4-³=
(1/2⁵) ÷ (1/4)³=
1/32 ÷ 1/64=
1/32 × 64/1=
64/32=
2
