Which of the following is not a factor that influences investment spending?

With heteroskedastic errors, the weighted least squares estimator is BLUE. You should use OLS with heteroskedasticity-robust standard errors because

A) this method is simpler. B) the exact form of the conditional variance is rarely known. C) the Gauss-Markov theorem holds. D) your spreadsheet program does not have a command for weighted least squares.

If a non-discriminating monopolist decides to lower its price to sell one more unit of its product, then

a. total revenue rises by an amount equal to the price b. some revenue is lost to the extent that units previously sold at a higher price now sell for a lower price; however, the additional unit sold brings in new revenue c. marginal revenue increases when total revenue increases d. the net effect on total revenue is typically zero since the price must fall e. the net effect on total revenue is typically negative since the price must fall