Answer:
By definition, the derivative of f(x) is

Let's use the definition for 

Then, 
It means to convert 3liters to mL
400g to kg
And so as the following
Answer:
25 minutes
Step-by-step explanation:
Let the amount of time, in minutes, be x.
For Container A, we can write:
200 + 6x [since it has 200 and is being filled with 6 per minute]
For Container B, we can write:
500 - 6x [since it has 500 and is being drained with 6 per minute]
To find, we equate them and solve for x:

<em>So, in 25 minutes (m), the two containers will have same amount of water</em>
4, -4
-5, 5
-2, 2
-(-7), -7
Hope this helped !