N = 46 Arithmetic Mean = 28.00 Standard Deviation = 25.92 Standard Error = 3.82 Null Hypothesis: H0 :20 = 0.10
df = 45 T Test Statistic = 2.09 p-value = 0.021
One-Tail Test Upper Critical Value = 1.3006 Decision = Reject.

1. The parameter the manager is interested in is:
a) the mean number of defective light bulbs per case produced at the plant.
b) the mean number of defective light bulbs per case among the 46 cases.
c) the mean number of defective light bulbs per case produced during the morning shift.
d) the proportion of cases with defective light bulbs produced at the plant.