The picture won’t load re upload it so I can answer.
It is 9 because you have a 30,60,90 triangle, and then you can use pythagorean theorem.
(x-30)+(x+76)=180
x-30+x+76=180
2x+46=180
2x=134
x=67
67-30=37
67+76=143
<1=37, <2=143
320 pounds of algea. After 4 hours, it would be 80, After 8 hours, 160. After 12 hours, 320
