Selecting surrogate variables works well if one factor loading for a variable is clearly higher than all other factor loadings

Which of the following would be considered a variable cost in a manufacturing setting?

A) direct labor B) insurance C) rent D) administrative salaries

What is a major drawback to the basic majority voting classification in kNN?

A) It requires frequent human subjective input during computation. B) Classes that are more clustered tend to dominate prediction. C) Even the naive version of the algorithm is hard to implement. D) Classes with more frequent examples tend to dominate prediction.