The biggest design innovation that SpaceX has pioneered is, of course, the fact that Dragon 2 is partially reusable, potentially resulting in a significant cost reduction. The first stage of the spacecraft is capable of re-entering the atmosphere and landing vertically after separating from the second stage.
Answer:
D nitrogen because it makes up most of our atmosphere
Sum of all angles in a quadrilateral is 360....so x=36
1st angle=4(36)=144
2nd angle=3(36)=108
3rd angle=2(36)=72
4th angle =36
