【简答题】A.Germans usually have a high respect for science. B.Einstein was forced to serve in the German army. C.Albert Einstein had no other interests besides science. D.Einstein's reputation was ruined becau...
【单选题】从均值为200,标准差为50的总体中抽取容量为100的简单随机样本,样本均值的数学期望是()
【单选题】在下列颜色中可以与紫色互为补色的是()。
【单选题】The comparison of rates of Swiss and Germans walk to work is used to illustrate______.
A.
the wide differences even in neighboring countries
B.
the different analyses of people' s habits
C.
the high rates of inactivity in two countries
D.
the worrying about their differences
【单选题】从均值为 200 ,标准差为 50 的总体中抽取容量为 100 的简单随机样本,样本均值的数学期望是