Answer:
It is 12. 12 fossils were found in Wyoming.
Step-by-step explanation:
Because a rectangular pyramid's base is square, the cross section would be as well
we know the perimeter is 24, and is an equilateral triangle, so it has three equal sides, so each side is 24 ÷ 3 = 8.

If it's for a graph then I believe you just find the slope which you can do by taking two points and plugging them into this equation y-y
/
X-X
Example: (2, 4) and (6, 7) the first number is always x and the second is always y so if you plug those in the equation would look like this....
4-7
/
2-6
That would end up being
3
- ---- aka the rate of change
4
P.s. The slash and the four dotted lines together means division. Hope this helps