Answer to Question 1
D
Market share is ratio data, and the sample size is over 30, so the z-test is appropriate.
Answer to Question 2
A contingency table is a data matrix that displays the frequency of some combination of possible responses to multiple variables. Two-way contingency tables, meaning they involve two less-than interval variables, are used most often. The row and column totals often are called marginals because they appear in the table's margins. Researchers usually are more interested in the inner cells of a contingency table because they display conditional frequencies (combinations). Using these values, we can draw more specific conclusions.
