Here are the answers:
1.) DC=D’C’
2.) 3.) ED=E’D’
The answer is A because there are only acute angles
Answer:. C is not a function.
Step-by-step explanation: If there is more than one y-value for each x-value, it can't be a function. The elipse has two y-values for each x.
Another triple integral. We're integrating over the interior of the sphere

Let's do the outer integral over z. z stays within the sphere so it goes from -2 to 2.
For the middle integral we have

x is the inner integral so at this point we conservatively say its zero. That means y goes from
and 
Similarly the inner integral x goes between 
So we rewrite the integral

Let's work on the inner one,

There's no z in the integrand, so we treat it as a constant.

So the middle integral is
I gotta go so I'll stop here, sorry.
You would need 13 cases. If you would like an explanation of my answer, let me know.