V=4/3πr^3, so substitute what you know. Input the volume so you only have to solve one variable, the r, radius.
Answer:

Step-by-step explanation:
Given

<em>See attachment for circle</em>
Required
Find 
From the attachment, we can see that:
is at the circumference
is in at the center
From cyclic theorems,
The relationship between ABC and ADC is:

Make ABC the subject

Substitute: 


Answer:
6^{4} · 4^{4} · b^{3}
Step-by-step explanation:
Collect identical number terms to get the exponent:
6.4⋅6.4⋅6.4⋅6.4⋅b⋅b⋅b
As you can see, there are four "6s", four "4s" and three "b"s
So we got the conclusion the answer is just 6^{4} · 4^{4} · b^{3}
I don’t think any of them are right