tolong di bantu dong

v balok 1= pxlxt.
=12x8x10
=96x10
=960
v balok 2= pxlxt
=12x8x20
=96x20
=1920
v balok 3=pxlxt
=12x8x30
=96x30
=2880
v balok seluruh=2880+1920+960
=4800+960
=5760