Suppose 120 geology students measure the mass of an ore sample. Due to human error and limitations in the reliability of the balance, not all the...

Suppose 120 geology students measure the mass of an ore sample. Due to human error and limitations in the reliability of the​ balance, not all the readings are equal. The results are found to closely approximate a normal​ curve, with mean 82 g and standard deviation 2g. Use the symmetry of the normal curve and the empirical rule as needed to estimate the number of students reporting readings between 78g and 86g.