When economists say that equilibrium is efficient, they mean that…?

The market for corn in country a is highly competitive. at the current market price of $5/bushel there is a shortage of 100,000 bushels of corn in this country. media reports claim that the price of corn will rise drastically in the near future. according to these reports, the neighboring country b had witnessed a similar situation recently. at the same price, the shortage in country b was also 100,000 bushels and eventually the equilibrium price in b went up to $10/bushel. both countries are known to have equal number of corn producers and the market supply of corn is identical at all prices. this, combined with the fact that consumers in the two countries also have similar tastes and preferences, led the media to conclude that the price of corn in country a would soon be as high as $10/bushel. the new equilibrium price turns out to be below $10/bushel, what inferences can be drawn?

Differentiate between the trait, behavioral, and results-based performance appraisal systems, providing an example where each would be most applicable.

What are the uses of national income data