1.2, the sample mean is 13.226, and the sample variance is 0.07053.
1, thinking 2:
The sample mean is 40.52, the sample variance is 4.64 1778, the sample standard deviation is 2. 154479, and the second-order central moment is 4. 1776.
Prove that the most annoying thing is to rely on yourself.
2.ADEFG is not a statistical data.
3. 1 obeys the chi-square distribution, with the expected value of 1 and the variance of 2; 3.2, the variance is 10.
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Too much. I don't have the time. I can only help you with this matter.