Why is it impossible to compute OLS estimators in the presence of perfect multicollinearity?

A. It is impossible to compute OLS estimators in the presence of perfect multicollinearity because it produces multiplication by 0.

B. It is impossible to compute OLS estimators in the presence of perfect multicollinearity because adding a new explanatory variable does not increase fit of the model.

C. It is impossible to compute OLS estimators in the presence of perfect multicollinearity because it produces division by 0.

D. It is impossible to compute OLS estimators in the presence of perfect multicollinearity because the conditional distribution of the error term has a nonzero mean.

Arival company manufactures fuel tanks for cars using a different production technique. the total weekly cost (in dollars) of producing x tanks is given by c(x) = 10000 +90x - 0.04x2 find the marginal cost at a production level of 500 fuel tanks per week to approximate the cost of the 501st unit (round to the nearest 2 decimal places, if needed)

In return for their with optimizing his painting project, the castle servant informed poly and digit that he saw someone dressed as the king leaving behind a trail of crumbs as he walked into the jester's room late last night. poly and digit have finally found the crisp-collecting culprit — it turns out the jester's shoe size and hair color match the clues that were found! in gratitude, poly and digit agree to the servant with his current task of replacing all of the tables and chairs in the castle. his goal is to determine which furniture company should produce the new furniture. he receives information from a company that customizes elegant furniture, and he wants to analyze the company's production process in order to calculate some problems about cost and availability. read the following scenario, and assist poly and digit as they the servant with his calculations. the fit for a king furniture company requires 2020 hours of labor to produce a standard table, and a chair requires 1212 hours of labor. the labor available is 565565 hours per week. the company can produce at most 3535 chairs per week.

The market demand curve for a popular teen magazine is given by q = 80 - 10p where p is the magazine price in dollars per issue and q is the weekly magazine circulation in units of 10,000. if the circulation is 400,000 per week at the current price, what is the consumer surplus for a teen reader with maximum willingness to pay of $3 per issue?