Will get brainiest, only 2 questions. will get an extra 40 points
1. explain why the outer planets did not lose the lighter gases in their atmosphere.
2. what are two major differences in the composition of the inner and outer planets?

1. They have more mass, thus more gravity. 
1a.) They are more distant from the Sun, so the solar winds that have stripped the atmospheres of Mercury and Mars, for example, down to practically nothing, are not as strong.

2.) Inner planets have hard, rocky surfaces and no rings. Outer planets have rings and are gassy!

therefore, the efficiency is: