Her neighbor could not afford to repair the roof on her house, so tijuana secretly hired and paid for a contractor to repair the roof. the neighbor never knew who was responsible. tijuana's actions are an example of

Tijuana's actions are an example of "altruism".

Altruism is carrying on of worry for another's prosperity. Regularly, individuals carry on charitably when they see others in edgy conditions and feel sympathy and a craving to help. Selflessness doesn't generally easily fall into place, since by definition, it expects individuals to slight their very own worries to help other people with no desire for remuneration, however "reciprocal altruism" is a term utilized by evolutionary scholars and analysts to describe the choice to help with a desire that one will get some advantage or result to oneself. Agreeable conduct enabled our predecessors to make due under brutal conditions, despite everything it fills an important need to an exceedingly mind boggling society.

a. money supply  

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