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:
B' (5,1)
C' (3,2)
A' (3,0)
Step-by-step explanation:
We know the measure of one of the angles.Angle b which is 90.
Now we have to find the other two angles.
First we will find angle a.
There are 180 degrees in a straight line.
Sooo...
180-130=50
Angle a will be 50.
There are also 180 degrees in a triangle.
To find the last angle we do this
180-50-71=59
Your answer and the measure of angle c will be 59 or option 3.