(ii) The family error rate is the probability of obtaining a significant result for at least one of the t -tests conducted, under the assumption that the null hypothesis is true. Use the tree diagram to determine the family error rate for two t -tests, each conducted at a level of α=0.05 . Show your work.

The accompanying normal probability plot was constructed from a sample of 30 readings on tension for mesh screens behind the surface of video display tubes used in computer monitors. does it appear plausible that the tension distribution is normal? the given probability is has a significant downward curve, so it is plausible that the tension distribution is normal. the given probability is has a significant downward curve, so it is not plausible that the tension distribution is normal. the given probability is quite linear, so it is plausible that the tension distribution is normal. the given probability is has a significant upward curve, so it is not plausible that the tension distribution is normal. the given probability is quite linear, so it is not plausible that the tension distribution is normal.