单选题
The following 10 observations are a sample drawn from an approximately normal population:
| Observation | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Value | -3 | -11 | 3 | -18 | 18 | 20 | -6 | 9 | 2 | -16 |
The sample standard deviation is closest to:
【正确答案】
C
【答案解析】
C is correct. The sample mean is:
The sample variance is:
The sample standard deviation is the (positive) square root of the sample variance.
