By definition, the volume of a cone is given by:

Where,
r: radius of the circular base
h: height of the cone
Let's define a variable:
x: diameter of the base
We have then that the radio is:

The height is:

Substituting values:

Rewriting:
Answer:
An expression that represents the volume of the cone, in cubic units is:
ANSWER
E. 10 and 640
EXPLANATION
The given series is

To find the first term of the series we substitute i=1 to get,


For the last term of the series, we substitute i=4 to obtain,


This implies that,

Therefore the correct answer is E
-6/7 because it’s rise over run, we are going down so it’s negative, 10 down and 9 to the left which is -0.9 and -6/7 it’s -0.857 and if we round this number we have -0.9 left
See the attached figure.
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AB = 10 , FD = 3
∵ D is the midpoint of AB, and F is the mid point of CB
∴ FD // AC , FD = 0.5 AC
∵ Δ ABC is a right triangle at C
∴ FD ⊥ BC
∴ BD = 0.5 AB = 5
∴ in Δ FDB ⇒⇒ BF² = BD² - FD² = 5² - 3² = 16
∴ BF = √16 = 4
∵ F is the mid point of CB
∴ CF = BF = 4 , and CB = 2 BF = 2*4 = 8
∵ D is the midpoint of AB, and E is the mid point of AC
∴ DE // CB , and DE = 0.5 CB = 0.5 * 8 = 4
∴ T<span>he length of line ED is 4
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8 boxes is 100%, 6 out of 8 is 6/8 x 100% = 75%