There can be many form of communication:
Like newspaper, emails, phone calls, social media, text messages etc.
I believe the answer is: scarcity and opportunity costs
A concert tend to happen on unpredicatble time, which make it considered to be scarce among fans. When we are forced to choose between going to concert or study, we would be forced to weigh the opportunity cost that arise when we sacrifice a certain option to pursue another, and choose the activity that give us the most benefit.
Answer:
Washingtons Right hand man. Eventually general at yorktown.
Explanation:
Answer: "family history of depression" .
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