Statistics students were asked to go home and fill a 1-cup measure with raisin bran, tap the cup lightly on the counter three times to settle the contents, if necessary add more raisin bran to bring the contents exactly up to the 1-cup line, spread the contents on a large plate, and count the raisins. For the 13 students who chose Kellogg’s brand the reported results were23 33 44 36 29 42 31 33 61 36 34 23 24(a) Construct a 90 percent confidence interval for the mean number of raisins per cup. Show your work clearly. (b) Can you think of features of the sample or data-gathering method that might create problems? If so, how could they be improved? (c) Identify factors that might prevent Kellogg’s from achieving uniformity in the number of raisins per cup of raisin bran. (d) How might a qualitycontrol system work to produce more uniform quantities of raisins, assuming that improvement is desired? Raisins