(+5)-(-4)= (ITA)= GIB4-1 (k)-(10) (+12)-(-5)- (+5)-(+15)= 12-(0)= 15-(+1)= 18-221- 15+(-3) + (-1) =( + DE 21-(-9)-(-9) (-1)= 10- (-8)-(-1) + 4 =​