The number of days' sales uncollected is calculated by:

A、dividing the covariance of the security with the market by the variance of the market.

B、dividing the correlation of the security with the market by the variance of the market.

C、dividing the variance of the market by the covariance of the security with the market.

D、dividing the variance of the market by the correlation of the security with the market.

A)美国约有四分之一是年轻人，他们既不读书，也不相信别人。

B)美国没有阅读能力的年轻人的数量令人难以置信地占了年轻人总数的四分之一。

C)大约有四分之一的美国年轻人没有阅读能力，这简直令人难以置信。

D)大约有四分之一的美国年轻人没有读过什么书，这简直令人难以置信。

A.expense is calculated using current tax rates with no adjustments.

B.liability and asset accounts are adjusted to reflect the new expected tax rate.

C.liability and asset accounts are maintained at historical tax rates until they reverse.

A、a. (marginal revenue) minus (average cost).

B、b. (average revenue) minus (average cost).

C、c. (marginal revenue) minus (marginal cost).

D、d. (price minus average cost) times (quantity of output).

A、a. ATC = (change in total cost)/(change in quantity of output).

B、b. ATC = (change in total cost)/(change in quantity of input).

C、c. ATC = total cost/quantity of output.

D、d. ATC = total cost/quantity of input.