The volume of the triangular prism = 
Thus the volume is
.
Thus the volume is 42 cubic km.
Hope that helps!
The answer to the problem is -5
Area=pir^2
diameter/2=radius
diameter=9
d/2=9/2=4.5=r
area=pi4.5^2
area=pi20.25
aproxpi=3.14
area=63.585
round hundreth
area=63.59
answer is 63.59cm^2
3(x+6)>8-(x-7)
3x+18>8-x+7
2x+18>15
2x>-3
X>-3/2