Caused because gravity pulls air down

Gravity is the force that keeps us attracted to objects with a larger mass than us. Earth has so much mass that we are stuck to it. If we jump up, we come down. If you throw a ball up in the air, it will come down unless you throw it with such force that it escapes the pull of the earth. Many things are caused by gravity.

Asmall closed hole formed in an outwash plain or moraine. forms when a  glacier retreats then remains stationary. 

Check -it can you examine advantages and drawbacks to possible solutions.check-it can you consider options to solve a problem.check-it can you persuade an audience to support a proposal.check-it can you identify the cause of a problem.