1. When an ecosystem changes, the results are a. Positive
b. Negative
c. Both
d. None

c, liquids evaporate, creating a gas

a polar bond is formed when electrons are shared unevenly between atoms

answer: any goods being imported from another country may be subject to issued by the federal government are tariffs

explanation:  

tariffs are a tax on anything that are imported from abroad. government use them to protect and boost their local industries and the thought is that they encourage consumers to buy local instead of importing and they will hope will protect jobs and economy in the country that implements them