For 3 sides to form a triangle two sides added together need to be greater then the 3rd side. You need to check all 3 combinations:
1. 11.5 + 10.5 = 22, 22> 6.1
11.5 + 6.1 = 17.6 17.6 > 10.5
10.5 + 6.1 = 16.6, 16.6 > 11.5
This one can make a triangle.
2. 9.5 + 3.5 > 4.5
9.5 + 4.5 > 3.5
4.5 + 3.5 < 9.5
Cannot make a triangle.
3. 8 + 6.7 > 1
6.7 + 1 < 8
Cannot make a triangle.
4. Can make a triangle
5. Can
6. Can
Answer:

Step-by-step explanation:
We have a 4-sided triangular pyramid
, where

N=d-2
q=n+d =>q=(d-2)=q=2d-2
25q+5n+10d=525
replace q and n with d
25(2d-2) +5(d-2)+10d=525
50d-50+5d-10+10d=525
65d=585
d=9
n=7
q=16
Yes because 26 is an even number
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