(1) According to the frequency distribution histogram, the frequency of the seventh group is F7 =1-(0.004+0.012+0.016+0.03+0.006+0.004) ×10 = 0.

The histogram is shown in the figure.

(2) The average score of this examination in our school is 65× 0.04+75× 0.12+85× 0.16+95× 0.3+105× 0.2+15× 0.00. ... (8 points)

(3) The sixth group consists of 3 people, respectively marked as A 1, A2 and A3, and the eighth group consists of 2 people, respectively marked as B 1 and B2;

So all the basic events of any two people are? (A 1，B 1)，(A 1，B2)，(A2，B 1)，(A2，B2)，(A3，B 1)，(A3，B2)，(A65438。

The score difference is above (10), which means that the two people come from different groups and have six basic items: (A 1, B 1), (A 1, B2), (A2, B 1), (A2.

So two people are randomly selected, and the probability that the difference is above (10) is p = 6 10 = 35.