(a) determine the probability that a random box of brand B raisins would fall between 25.8 and 29.4 (within one standard deviation of the mean)
(b) calculate the values that are two standard deviations away from the mean. Sketch them on the graph.
(c) determine the probability that a random raisin box would fall within two standard deviations of the mean. 
(d) Repeat steps b and c for raisin boxes that fall within three standard deviations from the mean.