A CI is desired for the true average stray-load loss (watts) for a certain type of

Question:

A CI is desired for the true average stray-load loss µ (watts) for a certain type of induction motor when the line current is held at 10 amps for a speed of 1500 rpm. Assume that stray-load loss is normally distributed with σ = 3.0.
a. Compute a 95% CI for m when µ = 25 and = 58.3.
b. Compute a 95% CI for m when µ = 100 and = 58.3.
c. Compute a 99% CI for m when µ = 100 and = 58.3.
d. Compute an 82% CI for m when µ = 100 and = 58.3.
e. How large must be if the width of µ the 99% interval for m is to be 1.0?