Which of the following materials is a substance? air gasoline stainless steel silver

The only material from this group that can be considered a substance is:

Silver.

Explanation:

To understand this answer we need to analyze something first. The substance is a concept that is very flexible in different disciplines. However, we need to clarify something. Substance from a chemical point of view is applicable for any kind of material that is not mixed with another one. And from all of these, only the silver is not mixed with other elements to exist.

3 hours because it is a decent distance.

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