Answer:

For this case we know that
represent the radius,
the height and the rate given is:


And replacing we got:

And that represent 
Step-by-step explanation:
For a tank similar to a cylinder the volume is given by:

For this case we know that
represent the radius,
the height and the rate given is:

For this case we want to find the rate of change of the water level when h =6m so then we can derivate the formula for the volume and we got:

And solving for
we got:

We need to convert the rate given into m^3/min and we got:

And replacing we got:

And that represent 
Answer:
7 ( b + 4 ) = 9
Step-by-step explanation:
Let the number be = b
It is given that the :
The number is added to 4.
And the value is equal to 9 when it is 7 times the sum of the number, b and 4.
Thus according to the question, the sentence can be translated in equation form as :
7 ( b + 4 ) = 9
Thus in other word, we can say that the addition of (b + 4) when it is multiplied for 7 times, we get the result as 9.
Answer:
A general exponential equation is written as:
f(x) = A*(r)^x
Where:
A is the initial value, this is the value that the function takes when x = 0.
r is the rate of growth
x is the variable.
In this case, the function is:
f(x) = 2*(4)^x
The initial value is:
f(0) = 2*(4)^0 = 2*1 = 2
The initial value is 2.
And the rate of growth is 4.
So Martin seems to mixed these two values (he said initial value = 4, and rate = 2, which is the opposite of what we found)
Multiply dc over one on both sides on the left it’ll be cancelled out with a alone and on the right it would be b*dc - from a freshman