Answer:
C. This was hard to do when I had this question
Step-by-step explanation:

It is probably random, since they are asking random users to identify new features they would use. :)
Answer:
Rock travels about 8.2x²meters higher on the moon than on the Earth.
Step-by-step explanation:
Expression showing the height of a rock thrown into the air at Earth is,
f(x) = -9.8x² + 10x + 1.5
Similarly, expression showing the height of rock thrown on the moon is,
g(x) = -1.6x² + 10x + 1.5
Difference in the height of the rock thrown on moon = g(x) - f(x)
= (-1.6x² + 10x + 1.5) - ( -9.8x² + 10x + 1.5)
= -1.6x² + 9.8x² + 10x - 10x + 1.5 - 1.5
= 8.2x²
Therefore, rock travels about 8.2x²meters higher on the moon than on the Earth.