30. items produced by a manufacturing process are supposed to weigh 90 grams. the manufacturing process is
such, however, that there is variability in the items produced and they do not all weigh exactly 90 grams. the
distribution of weights can be approximated by a normal distribution with mean 90 grams and a standard
deviation of 1 gram. about what percentage of the items will either weigh less than 87 grams or more than
93 grams?
a 0.15%
b. 0.3%
c. 6%
d. 94%
e. 99.7%