A sample of 25 resistors, each labeled 100(, had an average resistance of 101.4( with a standard

Question:

A sample of 25 resistors, each labeled 100(, had an average resistance of 101.4( with a standard deviation of 2.3(. Assume the resistances are normally distributed.
a. Find a 95% prediction interval for the resistance of a single resistor.
b. Find a tolerance interval for the resistance that includes 90% of the resistors with 95% confidence?