I am having trouble. Help me, please!

1). A sample of 60 freshmen from University X had a mean GPA of 2.8 over all their courses taken in their first semester at the university. This had a variance of 25. Perform a hypothesis test at the 0.05 significance level to test the claim that the first semester GPA of all OU freshmen is less than a B (3.0). 2). In a random sample of 300 patients, 21 experienced nausea. A drug manufacturer claims that fewer than 10% of patients who take its new drug for treating Alzheimer's disease will experience nausea. Test this claim at the 0.05 significance level. 3) The amount of water consumed each week by residences of City X is normally distributed. A simple random sample of 10 residences was taken with a sample mean of 120.3 gallons and a standard deviation of 10.0 gallons. Test the claim at the 0.10 significance level that the average amount of water consumed is not 125 gallons. For each of the scenario, write the null hypothesis and the alternative hypothesis (mathematical expressions) separately. Then calculate the test statistics for each scenario (Make sure you use the correct test statistics as z or t)