V = 4πr³/3
Substituting,
V = (4/3)π(3 cm)³
V = 36π cm³
Answer:
The answer is C
Step-by-step explanation:
<span>Rate of pump A: 1/8 of a pool per hour
Rate of pump B: 1/9 of a pool per hour
Combined rate: 1/8+1/9 = 17/72 +1/9 = 25/72
So if they work together, the two pumps have a combined rate of 25/72 of a pool per hour (i.e in one hour, the two pumps will empty 25/72 of the pool)
</span><span>But we want to empty ONE pool (not 25/72 of one). So we need to multiply 25/72 by some number x to get 1.
</span>
<span>Now solve for x
x=2.88
</span><span>It will take the two pumps 2.88 hours to empty the pool.
2 hours 52 minutes 50 seconds</span>
The solution to your problem about the probability <span>of getting first a red and then a black marble is as follows:
</span><span>(3 red / 8 total) * (2 black / 7 total) = 3/28
</span>
Therefore, the probability of getting first a red and then a black marble is 3/28.
I hope my answer has come to your help. Thank you for posting your question here in Brainly.
