请教一下level 1的几道题

1. Which of the following would be counted as frictional unemployment?

A. Due to the negative growth of GDP, Smith was laid off.

B. Johnson was fired from his job after he got into an argument with his foreman, and has not sought a new job.

C. Although there were jobs available, Jones was unable to find an employer with an opening.

D. When the plant was modernized, Jones lost her job because she did not have the skill needed to operate the new equipment.

Answer: C

请问，难道B不属于frictional unemployment?

2. For a demand-pull effect or a cost-push effect to cause inflation:

A. the AS curve has to shift in response to a shift of the AD curve.

B. the AD curve has to shift in response to a shift of the AS curve.

C, the cause of the shift in AD or AS must be repeated or sustained.

D. economic equilibrium must be re-established at a higher price level.

Answer: C

没有明白为什么是C，难道不是D吗？

先谢谢了：）