a) +5+9(-9)-(+4)+(-13)-(-7)+(-8)=
= 5-81-4-13+7-8
= -94
b) -8+(+4)-(-2)+(-15)-(+10)+(-11)=
= -8+4+2-15-10-11
= -38
c) -14+(-18)-(+3)+(+12)-(-9)+(-17)=
= -14-18-3+12+9-17
= -31
d) 10+(-11)-(+7)+(-3)-(-12)+(-4)=
= 10-11-7-3+12-4
= -3
e) +7+(-8)-(+5)+(-12)-(9)+(-6)=
= 7-8+5-12-9-6
= -23
f) -9+(+5)-(-3)+(-16)-(+11)+(-10)=
= -9+5+3-16-11-10
= -38
g) -15+(-18)-(+4)+(+11)-7(-7)+(-19)=
= -15-18-4+11+49-19
= 4
h) 12+(-13)-(+8)+(-4)-(-15)+(-6)=
= 12-13-8-4+15-6
= -4
i) 14+(-2+3-5)-(-7+4-6)=
= 14+(-4)-(-9)
= 14-4+9
= 19
j) -23-(10-9+3)+(12-19+3)=
= -23-4+(-4)
= -23-4-4
= -31
k) 21+(-13+7-9)-(-11+9-2)=
= 21+(-15)-(-4)
= 21-15+4
= 10
l) -17+(-9+18-13)-(15-10+7)=
= -17+(-4)-12
= -17-4-12
= -33
m) 27-(3+20-9)+(-18+5-2)=
= 27-14+(-15)
= 27+14-15
= -2