64 as it’s multiplied by 2 each time
Answer:
Height = 8 cm
You will need this formula (see attached):
Volume = [PI * 8 * (2² + 2*4 + 4²)] / 3
Volume = [3.14159265 * 8 * (4 + 8 + 16)] / 3
Volume = 234.57 cubic centimeters
Source: http://www.1728.org/volcone.htm
Step-by-step explanation:
When x=-1:

Ok that gives us a little more information.
If we implicitly differentiate with respect to t, from the very start, then we can apply our product rule, ya?

The right side is zero, derivative of a constant is zero.
Where x' is dx/dt and y' is dy/dt.
From here, plug in all the stuff you know:
y' = -3
x = -1
y = 4
and solve for x'.
Hope that helps!
I also think its 4 but im not sure