After 12 hours the pound would have 720 pounds of algae.
15) Basically, this year Chelsea is making 64 cups of soup, and since there are 16 cups in a gallon, Chelsea will make 4 gallons.
16) Option D
Answer:

Step-by-step explanation:

Hope this helps!
volume of a sphere is 4/3 * PI * r^3
r = 6
r^3 = 6^3 = 216
4/3 * 216 = 288
Volume = 288 PI in^3