There are just two areas with the same vaccine batch number, and the number of species is C32A42=36, (3 points).
The probability of selecting the same vaccine batch number in exactly two of the three districts is p = 916; (6 points)
(two) the number of areas with the same vaccine batch number. Possible values are 0, 2, 3, (8 points).
p(ζ= 0)= a 3443 = 38，p(ζ= 2)= 9 16，p(ζ= 3)= c 1443 = 1 16，(65438。
The distribution list is:
eξ= 0×38+2×9 16+3× 1 16 = 2 1 16。 (12)