If I chose to go to the hockey game instead of going to the movies what is my opportunity cost?

Explanation:

If you choose to go to the hockey game instead of going to the movies, your opportunity cost is seeing a movie, getting popcorn at the movies, etc, you chose the opportunity to see a hockey game and lost the opportunity to see a movie.

a social contract.

"a social contract is an agreement between citizens and their leader where the citizens give up certain freedoms in exchange for protection. the constitution of the united states is an example of a social contract."

the allies' desire to seek retribution for germany's actions