Long Riddles and Answers

Question: What arrives at the end and can occur several times a day, once every month, or last millions of years?

Question: Travel a mile and I will change.
Travel a million and I will end as I started.

What am I?

Question: A man pushes his car and stops in front of a hotel and immediately goes bankrupt. What is he doing?

Question: Mary gets in the shower, but surprisingly her hair is not wet when she gets out. How is this possible?

Question: Under pressure is the only way I work,
and by myself is the only way I'm hurt.

What am I?