Economists state that every decision involves trade-offs. economists measure and define these trade-offs as: a. productions possibilities curve. c. circular flow of economic activity. b. paradox of value. d. opportunity costs. select the best answer from the choices provided

Option D i.e Opportunity Costs is the correct answer.

Economists define trade-offs in simple terms as a situational decision where a person chooses a thing over the sacrifice of another thing,owning to limited resources and time.

Opportunity Cost of a choice is what you gave up to get it. For example, you gave up the idea of watching movie tomorrow in order to go for a dinner.

alliances in ww1 were different from ww2 because the entente in ww1 made up of serbia,russia,france,britan,japan and italy later america  and all allied in a sort of balance of power and too keep germany,austria-hungary,and the ottomans down. russia allied the serbians in order to exert its influence in the balkans while france allied the russians because france was still in dismay and insulted after the defeat to the germans during the unification of germany and britian allied the belgians after the germans invasion of belgium.in ww2 the alliances were in a preemptive attempt to deter any further wars into happening while germany and italy allied since they were insulted and humiliated after the previous war while also sharing a similar ideology of facsim along with japan which all 3 had a want for world domination and agreed to assist one another in the endevours 

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