Answers and Explanations

SOLID GEOMETRY FOLLOW-UP TEST

1 . A

The formula for the lateral surface area    of  a   cone    is  in  terms   of  c   =   circumference   and ℓ   =

slant   height. You can use the given   base    radius  to  solve   for the slant   height:

You can think   of  the slant   height  as  the hypotenuse  of  a   right   triangle    whose   legs    are the

base    radius  and height  of  the cone.

Now you can see that    the triangle    is  a   3-4-5   and that    h   =   8.  Plug    r   =   6   and h   =   8   into    the

volume  formula: