4. A paint manufacturer wishes to validate its advertisement statement that a gallon of its paint covers on average more than 400 square feet.  An independent testing laboratory is hired to evaluate the advertisement statement based on fifty 1-gallon cans of paint randomly selected from the manufacturer’s warehouse. (Data is not shown, but use JMP output to answer these questions)

a. What is the research hypothesis that the manufacturer wants to test?  Write out the null and alternative hypothesis being tested

b. Is this data skewed left, skewed right, or symmetric?

c. Using the appropriate test for the research hypothesis, what can the paint manufacturer claim about the advertisement of covering at least 400 square feet?