Answers:
C. The Maximum height of the egg occurs at x=0.
D. The egg is in the air for 2 seconds.
E. The maximum height of the egg is 64 feet.
Explanation:
You can see that when X=0 the egg is currently at the point (0,64), which would be the maximum height for the egg. The maximum height of the egg occurs at X-0.
You can see that from X=0 to X=2 it had only been 2 seconds (according to your graph) which would be when it hit the floor. Hence, the egg is in the air for only 2 seconds.
And for problem E. As I explained in the first sentence the maximum height of the egg is at point (0,64) so yes the maximum height of the egg is 64 feet.
Hope I helped :)