Given a sample of n=10n=10n=10 with ∑xi=100\sum x_i = 100∑xi=100 and ∑xi2=1200\sum x_i^2 = 1200∑xi2=1200, what is the sample variance s2s^2s2?
252525
202020
2.222.222.22
22.2222.2222.22