Please help me! due last week! I need help asap! :)

1)  The formula for the volume of a right pyramid is 1/3* the area of the base * the height of the pyramid.  In this case, the base is a triangle, so our formula looks like this:
V=1/3(1/2bh)(H)
=1/3(1/2)(9)(15)(32)
=720 cm³.
2)  The formula for the volume of this square pyramid is V=1/3lwh.  Substituting our information we have:
V=1/3(18)(18)(12)
=1296 cm³
3)  The formula for the volume of any cone, oblique or right, is V=1/3πr²h.  Substituting our information, we have:
V=1/3π(6²)(10)
=1/3π(360)
=120π cm³
4)  Using our cone formula, V=1/3πr²h, we have:
V=1/3π(10²)(9)
=1/3π(900)
=300π cm³