A recent national survey found that high school students watched an average (mean) of 7.2 DVDs per month with a population standard deviation of .90. A random sample of 35 college students revealed that the mean number of DVDs watched last month was 6.20. At the .05 significance level, can we conclude that college students watch fewer DVDs a month than high school students?
a)State the null hypothesis and the alternate hypothesis.
b)State the decision rule.