If n samples are extracted from any population with mean value [img=11x18]1803dc1a4012523.png[/img] and variance [img=18x22]1803dc1a48a9511.png[/img], then A: When n is sufficiently large, the distribution of sample mean is approximately normal distribution. B: When n<10, the distribution of sample mean is approximately normal distribution. C: The distribution of sample mean is nothing to do with n. D: No matter how big n is, the distribution of the sample mean is not going to be close to a normal distribution.

‏Pair is not in complementary distribution.‌ A: spot and pot B: stop and top C: school and cool D: light and glad

Theoretically, the mean, median, and mode are all equal for a normal distribution.

The clear /l/ and the dark /f/ are __________. A: in complementary distribution B: in free variation C: both A and B D: neither of the two

Some important characteristics of population include ___________. A: genetics B: natality and mortality C: sex ratio and age distribution D: density and spatial distribution.