Answer:
7.5 m 457.5

Step-by-step explanation:
First, visualize the original cone and the smaller cone as overlapping similar triangles. The scale factor of the original cone to the smaller cone is 50:40, so if the smaller cone has a radius of 6 m, then the radius of the original cone would be 7.5 m.
The volume of the frustum is the volume of the original cone minus the volume of the smaller cone. The formula for the volume of a cone is V =
.
Original Cone =
=
= 937.5
Smaller Cone =
=
= 480
Frustum = 937.5
- 480
= 457.5
Let's call our number <em>x</em>.
So we can setup the equation x² = 100.
To solve this equation, we square root both sides.
So we have x = ±10.
Always use plus or minus when square rooting both sides
of an equation so our answer is not only 10, it's also -10.
Velocity
Formula wise:
1/2 x mass x velocity^2
(20:4)x3=15 (Ellas grade)
(20:5)x4=16 (Minhs grade)