Answer:
![V=5\sqrt{3}\ m^3](https://tex.z-dn.net/?f=V%3D5%5Csqrt%7B3%7D%5C%20m%5E3)
Step-by-step explanation:
we know that
The volume of a trough is equal to
![V=BL](https://tex.z-dn.net/?f=V%3DBL)
where
B is the area of equilateral triangle
L is the length of a trough
step 1
Find the area of equilateral triangle B
The area of a equilateral triangle applying the law of sines is equal to
![B=\frac{1}{2} b^{2} sin(60\°)](https://tex.z-dn.net/?f=B%3D%5Cfrac%7B1%7D%7B2%7D%20b%5E%7B2%7D%20sin%2860%5C%C2%B0%29)
where
![b=2\ m](https://tex.z-dn.net/?f=b%3D2%5C%20m)
![sin(60\°)=\frac{\sqrt{3}}{2}](https://tex.z-dn.net/?f=sin%2860%5C%C2%B0%29%3D%5Cfrac%7B%5Csqrt%7B3%7D%7D%7B2%7D)
substitute
![B=\frac{1}{2}(2)^{2} (\frac{\sqrt{3}}{2})](https://tex.z-dn.net/?f=B%3D%5Cfrac%7B1%7D%7B2%7D%282%29%5E%7B2%7D%20%28%5Cfrac%7B%5Csqrt%7B3%7D%7D%7B2%7D%29)
![B=\sqrt{3}\ m^{2}](https://tex.z-dn.net/?f=B%3D%5Csqrt%7B3%7D%5C%20m%5E%7B2%7D)
step 2
Find the volume of a trough
![V=BL](https://tex.z-dn.net/?f=V%3DBL)
we have
![B=\sqrt{3}\ m^{2}](https://tex.z-dn.net/?f=B%3D%5Csqrt%7B3%7D%5C%20m%5E%7B2%7D)
![L=5\ m](https://tex.z-dn.net/?f=L%3D5%5C%20m)
substitute
![V=(\sqrt{3})(5)](https://tex.z-dn.net/?f=V%3D%28%5Csqrt%7B3%7D%29%285%29)
![V=5\sqrt{3}\ m^3](https://tex.z-dn.net/?f=V%3D5%5Csqrt%7B3%7D%5C%20m%5E3)