Draw two lines and a transversal...
picture:

Explanation:

It might help to move either line m or line n to make them parallel to one another. This isn't required but it might help to see the answer better.

Angles 1 and 2 are between lines m and n, so they are interior angles. They are alternate interior angles as they are on alternate sides of the transversal line.

Angles 2 and 3 are on the same side of the transversal, and both are above their adjacent parallel line counterpart, so they are corresponding angles.

Angles 3 and 4 are outside the interior region, and they alternate on either side of the transversal. They are alternate exterior angles.

Angles 1 and 4 are corresponding for similar reasons as angles 2 and 3 are.

Notes:

(a) the volume of the cone is 20/3 in3

hence, option a is correct.