The moon, on the other hand, is very close to Earth, so appears to move relatively quickly across the sky. ... Astronomers measure distances in the sky in degrees, a complete circle being 360 degrees. The moon takes 27.3 days to complete its 360-degree trip around the sky, so moves 13.2 degrees in one night.
Answer:
in first blank :-answer is (is constant)
in second :- more expensive..
Science uses experiments to support its explanation
hope this helps
