I need help i dont under stand it

An externality can be created by a. people working at a production job and enjoying their work b. a production activity but not a consumption activity c. a consumption activity but not a production activity d. a production activity or a consumption activity externalities a. are always positive, and an example is flu vaccinations b. are always negative, and an example is the pollution created by trucks c. can be negative or positive. logging has a negative externality, and education has a positive externality d. can be negative or positive. a negative externality is having to go to school when you would rather go to the beach, and a positive externality is spending time with your friends

The economy of the united states is best described as

1. how did conditions in germany and europe at the end of world war i contribute to the rise and triumph of nazism in germany? 2. how did the german government under nazi rule build support among the german people? 3. how did nazi germany gradually isolate, segregate, impoverish, and incarcerate jews and persecute other perceived enemies of the state between 1933 and 1939? 4. how did the nazis lead germany to war in europe and, with their collaborators, kill millions—including systematically murdering six million jewish people? 5. why is learning about the holocaust important? so we don’t repeat history.