the normal distribution

A machine fills bags of potato chips. The weights of the filled bags are approximately normally distributed with mean 16 ounces and standard deviation 0.3 ounce. Any bag that weighs less than 15.5 ounces is rejected by an automatic scale at the end of the production line. Which of the following is closest to the proportion of the filled bags that are rejected?

A bottling plant fills bottles of spring water. The volumes are approximately normally distributed with mean 500 milliliters (mL) and standard deviation 4 mL. In the plant's quality report, each inspected bottle is listed with the z-score of its volume. One bottle is listed with a z-score of $-1.75$. How many milliliters of water does this bottle contain?