How did the "era of good feelings" emerge? what factors led to its demise? do you think it would be possible to have another "era of good feelings" now or in the future?

The Era of Good Feelings was the name applied to the period in the United State corresponding with the term of President James Monroe from 1817 to 1825. This marked a period that reflected a sense of national purpose and desire  at he end of the war of 1812.

This Era saw a brief full lull in the bitter partisan disputes that had plagued the democratic republican and federalist parties.

The political factor referred to the its demise was the very controversial election of 1824 which became known as the corrupt bargain brought an end to this period.

It's difficult to ensure that it may be happens again because it is depend of many causes. In that time was the effects of the war which motivated it.  Nowadays may be  the economic situation the reason to have another Era of Good Feelings.

the answer is b. 300t + 3/2xt

by creating a labor shortage that pushed the continent toward a market economy