Steel rods are manufactured with a mean length of 25 centimeters (cm). Because of

variability in the manufacturing process, the lengths of the rods are approximately normally

distributed, with a standard deviation of 0.07 cm. a) What proportion of the rods shorter than

24.9cm? b) Any rods that are shorter than 24.85 or longer than 25.15 cm are discarded. What

proportion of rods will be discarded?