Automatic shutoff valves can prevent extensive water damage from plumbing failures. The valves contain sensors that cut off water flow in the event of a leak, thereby preventing flooding. One important characteristic is the time (in milliseconds) required for the sensor to detect the water leak. Sample data obtained for four different shutoff valves are contained in the file titled Waterflow.

a. Produce the appropriate ANOVA table and conduct a hypothesis test to determine if the mean detection times differ among the four shutoff valve models.

Use a significance level of 0.05.

b. Use the Tukey-Kramer multiple comparison technique to discover any differences in the average detection times. Use a significance level of 0.05.

c. Which of the four shutoff valves would you recommend? State your criterion for your selection.