State whether each situation has independent or paired (dependent) samples.

a. A researcher wants to compare food prices at two grocery stores. She purchases 20 items at Store A and finds the mean and the standard deviation for the cost of the items. She then purchases 20 items at Store B and again finds the mean and the standard deviation for the cost of the items.

b. A student wants to compare textbook prices at two bookstores. She has a list of textbooks and finds the price of the text at each of the two bookstores.