1. has the advantage of men.
Connecting a 1, a2 and A4, A5, a6 and A7 can form four triangles.
Connect a2 and a3 with A8, A5, A6 and A7 to get four triangles.
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* * * Eight groups, 8*4=32.
2. There are two aspects.
Connecting A 1, A2 and A3 can make 1 triangles.
Connecting A2, A3 and A4 can make 1 triangle.
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Connecting A8, A 1 and A2 can make 1 triangles.
* * * Eight groups, 8* 1=8.
In a word, ***32+8=40.