A study was conducted to examine the number of rain days in July. Three cities A, B, C are selected, and the number of rain days in July from year 2001 - 2005 were recorded. Assume the samples are independent.

A: 3, 5, 4, 5, 6

B: 6, 8, 7, 9, 10

C: 3, 5, 2, 1, 6

1.(6) Is there any evidence to suggest that at least two cities mean number of rain days in July are different? Use=0.05.

=0.05.

2.(4) Calculate the 95% Bonferroni confidence intervals for all pairs comparisons, and identify which pair has significant difference. Note:

0.0083

(12)=2.7816

t0.0083(12)=2.7816. (t to the subscript of 0.0083(12) = 2.7816)