14. It's finding volume. The depth of the water is the value for the height.
15. I believe it's C
The answer is 28. My answer is correct. 7, 14& 21 can't be the LCM son the answer should be 28.
Answer:

Step-by-step explanation:





First step: Find out the prime numbers that make up the radical, for example, 120 would be 2x2x2x5x3
Second step: If there is 2 of the same number that repeats just put that number in the front of the resulting radical
Third: Just multiply the remaining radicals together and put the number in front of it.
Now you have