问题
单项选择题
In order to test whether the mean IQ of employees in an organization is greater than 100, a sample of 30 employees is taken and the sample value of the computed test statistic, tn-1=3.4. The null and alternative hypotheses are:（）
A. H0:μ=100; Ha:μ≠100.
B. H0:μ≤100; Ha:μ＞100.
C. H0:μ=100; Ha:X≠100.
答案
参考答案：B
解析：
The null hypothesis is that the theoretical mean is not significantly different from zero. The alternative hypothesis is that the theoretical mean is greater than zero.