The ACT is a college entrance exam. ACT has determined that a score of 22 on the mathematics portion of the ACT suggests that a student is ready for college-level mathematics. A high school teacher believes that the actual average ACT MATH score is higher than 22. He takes a random survey of 100 students who completed the ACT MATH test. The sample mean is 22.6 with a standard deviation of 3.9. Do we have strong evidence to support the teacher's hypothesis? Use 5% level of significance.