A paint manufacturing company claims that the mean drying time for its paints is not longer than 45 minutes. A random sample of 20 gallons of paints selected from the production line of this company showed that the mean drying time for this sample is 49.50 minutes with a standard deviation of 3 minutes. Assume that the drying times for these paints have a normal distribution.
a. Using the 1% significance level, would you conclude that the company's claim is true?
b. What is the type I error in this exercise? Explain in words. What is the probability of making such a error?