Many companies are becoming involved in flextime, in which a worker schedules his or her own work hours or compresses work weeks. A company that was contemplating the installation of a flextime schedule estimated that it needed a minimum mean of 7 hours per day per assembly worker in order to operate effectively. Each of a random sample of 90 of the company's assemblers was asked to submit a tentative flextime schedule. If the mean number of hours per day for Monday was 6.7 hours and the standard deviation was 2.1 hours, do the data provide sufficient evidence to indicate that the mean number of hours worked per day on Mondays, for all of the company's assemblers, will be less than seven hours? Test using a = 0.05. (Round your answers to two decimal places.) 1-2. Null and alternative hypotheses: O Ho: M = 7 versus Ha: H > 7 OH: u # 7 versus Ha: H = 7 OH: M 7 OH: u = 7 versus Ha: 1 = 7 O Ho:M = 7 versus Ha: u 5.97 O Ho: Ml 5.97 Find the test statistic and rejection region. (Round your answers to two decimal places. If the test is one-tailed, enter NONE for the unused region.) test statistic rejection region ZIndependent random samples of 36 and 46 observations are drawn from two quantitative populations, 1 and 2, respectively. The sample data summary is shown here. Sample 1 Sample 2 Sample Size 36 46 Sample Mean 1.29 1.32 Sample Variance 0.0570 0.0530 Do the data present sufficient evidence to indicate that the mean for population 1 is smaller than the mean for population 2? Use one of the two methods of testing presented in this section. (Round your answer to two decimal places.) Z = Explain your conclusions. O Ho is rejected. There is sufficient evidence to indicate that the mean for population 1 is smaller than the mean for population 2. O Ho is rejected. There is insufficient evidence to indicate that the mean for population 1 is smaller than the mean for population 2. O Ho is not rejected. There is insufficient evidence to indicate that the mean for population 1 is smaller than the mean for population 2. O Ho is not rejected. There is sufficient evidence to indicate that the mean for population 1 is smaller than the mean for population 2. You may need to use the appropriate appendix table or technology to answer this question.An experiment was planned to compare the mean time (in days) required to recover from a common cold for persons given a daily dose of 4 mg of vitamin C, u,, versus those who were not given a vitamin supplement, My . Suppose that 33 adults were randomly selected for each treatment category and that the mean recovery times and standard deviations for the two groups were as follows. No Vitamin 4 mg Supplement Vitamin C Sample size 33 33 Sample mean 6.9 5.3 Sample standard deviation 2.9 1.6 (a) Suppose your research objective is to show that the use of vitamin C reduces the mean time required to recover from a common cold and its complications. Give the null and alternative hypotheses for the test. OH: (1 1 - 12) = 0 versus Ha: (H1 - 12) = 0 OH: ( 1 1 - 12) = 0 versus Ha: (M1 - #2) 0 O Ho: (1 1 - H2) = 0 versus Ha: (H1 - #2) = 0 Is this a one- or a two-tailed test? O one-tailed test O two-tailed test (b) Conduct the statistical test of the null hypothesis in part (a) and state your conclusion. Test using a = 0.05. (Round your answers to two decimal places.) Z =