They could have assembled total 336 different possible crews.
<em><u>Explanation</u></em>
Total number of trained pilots is 9 and geologists is 4.
The crew should be consisted of 2 pilots and 1 geologist. That means, <u>2 pilots are chosen from total 9 and 1 geologist is chosen from total 4</u>.
Number of ways for choosing 2 pilots from 9
and
Number of ways for choosing 1 geologist from 4 
So, the total possible number of different crews they could have assembled 
B or c that’s feels the most likely to be it
To solve this you would use the pythagorean theorem since the brace is making the frame look like two right triangles. The theorem states that for a triangle with a right angle, A^2+B^2=C^2. A and B are the sides of the frame and C is the brace which is like the hypotenuse of the triangle. It doesn't matter which side is A or B so you can put 6 or 8 in place of either in the equation. 6^2+8^2=C^2. If you simplify this it equals 36+64=C^2, which then simplifies to 100=C^2. Then you take the square root of both sides (what number multiplied by itself = the number you are trying to get, in this case, 100). So then you get C=10 because 10x10=100. So the length of the diagonal brace is 10ft.
The factors of 56: 1; 2; 4; 7; 8; 14; 28; 56
The factors of 84: 1; 2; 3; 4; 6; 14; 28; 42; 84
GCF(56; 84) = 28