Let the observations xi(1 ≤ i ≤ 10) satisfy the equations, ∑(xi - 5) for i∈[i=1, 10] = 10 and ∑(xi - 5)2 for i∈[i=1, 10] = 40. If μ and λ are the mean and the variance of the observations, x1 - 3, x2 - 3, x10 - 3, then the ordered pair (μ, λ) is equal tp:
(1) (6, 6)
(2) (3, 6)
(3) (6, 3)
(4) (3, 3)