Using the large sample confidence interval formula for the mean, compute a 95%

confidence interval for the mean when

(a) ???? = 217, ????̄ = 283.9, and ???? = 35.6.

(b) ???? = 333, ????̄ = 7.8, and ???? = 1.3.

(c) ???? = 156, ????̄ = 764.2, and ???? = 108.1.