I just have these questions that I cant find in the book can someone please help.

When is it appropriate to include sunk costs in the evaluation of a project?

a. Include sunk costs if they improve the projects NPV.

b. Include sunk costs if they are considered to be overhead costs.

c. Include sunk costs when they are relatively large.

d. It is never appropriate to include sunk costs.

The standard deviations of individual stocks are generally higher than the standard deviation of the market portfolio for which of the following reasons?

a. Individual stocks offer higher returns.

b. Individual stocks have no diversification of risk.

c. Individual stocks do not have unique risk.

d. Individual stocks have more systematic risks.