please dijawab gunakanlah sifat perkalian (sifat komutatif,asisiatif,dan sifat tertutup

1.-3×6×(-4)=
-19×(-4)=76
2.7×12×(-5)=
84×(-5)=240
3.-10×(-3)×2=
30×2=60
4.15×(-2)×(-6)×3=
-30×(-6)×3=
180×3=540
semoga membantu