Questions 8 and 9 are based on the following information:
A local retail business wishes to determine if there is adifference in the mean preferred indoor temperature between men andwomen. Assume that the population standard deviations of pre-ferred temperatures are equal between men and women. Twoindependent random samples are collected. Sample statistics ofpreferred temperatures are reported in the table below.
| Sample Size | Mean (In Celsius) |
| Men (Group 1) | 25 | 22.5 |
| Women (Group 2) | 22 | 20.1 |
Standard deviation : Men: 1.2. Women : 1.4
In testing whether two population means are different, the valueof test statistic is .
A. 1.255
B. 1.378
C. 1.405
D. 1.578
Suppose that we perform a two-tailed test of the difference ofpopulation means, which of the following is the correctconclusion?
A. At the 0.20 significance level, we reject the nullhypothesis, there is a difference in the preferred indoortemperature between men and women.
B. At the 0.10 significance level, we reject the nullhypothesis, there is a difference in the preferred indoortemperature between men and women.
C. At the 0.10 significance level, we fail to reject the nullhypothesis, since the test statistic is smaller than the criticalvalue 1.645.
D. There is in sufficient evidence to draw a conclusion on thetest.
