The critical value is 1.684 unfounded, thank you

Question / 12 pts Pulse Rates of Women. A simple random sample of 40 women results in a standard deviation of 11.6 beats per minute (based on the data set provided). The normal range of pulse rates of adults is typically given as 60 to 100 beats per minute. If the range rule of thumb is applied to that normal range, the result is a standard deviation of 10 beats per minute. Use the sample results with 0.05 significance level to test the claim that pulse rates of women have a standard deviation greater than 10 beats per minute