Using the ExamScores dataset, a teacher found that the mean score for Exam2 is 79.4, which is below the expected mean of 83. At the =0.05 significance level, does sufficient evidence exist that the mean score of the class is lower than the expected mean? Use the output below.

Mean 79.4

Variance 205.4386

Observations 50

Hypothesized Mean 83

df 49

tStat -1.77606

P(T<=t) one-tail 0.040966

t Critical one-tail 1676551

P(T<=t) two tail 0.081933

t Critical two tail 2.0009575

1)

What is the null hypothesis H0?

2)

What is the alternative hypothesis Ha?

3)

What is the p-value?

4)

What is the conclusion for the t-test