Explain why it is important to understand if a map direction is based on true north or magnetic north?

I think that its important because when we get lost we dont know the true north or magnetic north. So we need to know about it

Air pollution: “combustion results in gases such as nitrogen oxides, nitrogen dioxide and particulates. the main causes of air pollution include transport, domestic combustion and industrial processes. pollutants from these sources can cause problems in the immediate vicinity and a distance away.”