A random sample of 250 observations was classified according to the row and column categories shown in the table

a. Do the data provide sufficient evidence to conclude that the rows and columns are dependent? Test using a = .05.

b. Would the analysis change if the row totals were fixed before the data were collected?

c. Do the assumptions required for the analysis to be valid differ according to whether the row (or column) totals are fixed? Explain.

d. Convert the table entries to percentages by using each column total as a base and calculating each row response as a percentage of the corresponding column total. In addition, calculate the row totals and convert them to percentages of all 250 observations.

e. Plot the row percentages on the vertical axis agains~
the column number on the horizontal axis. Draw horizontal lines corresponding to the row total percentages. Does the deviation (or lack thereof) of the individual row percentages from the row total per-
. centages support the result of the test conducted m part a?