Which two cosmologist hypothesized why the planets sometimes appear to move backward in the sky?

The softest and hardest minerals are: softest hardest

When you jump from an elevated position you usually bend your knees upon reaching the ground. by doing this, you make the time of the impact about 10 times as great as for a stiff-legged landing. in this way the average force your body experiences is a) less than 1/10 as great. b) more than 1/10 as great. c) about 1/10 as great.d) about 10 times as great.

Apersons beliefs and general outlook, which act like filters on the information they receive are called ?