[see picture link]Area of part 1:A1=base*height/2=(8+2)*(8-2-2-1)/2=10*3/2=15 ft^2Area of part 2:A2=length*width=(8+2)*1=10 ft2Area of part 3:A3=length*width=8*2=16 ft2
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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:
21 students
Step-by-step explanation:
25% of 28 is 7 28-7=21
Answer:
The answer is 4 cm
Step-by-step explanation:
The answer is 4 cm because the formula for a cone is V=π r^2 h/3, and the formula for a cylinder is V=π r^2 h, and the cone's volume is V≈301.59, and, a cylinder with
r=4 and h=6 is V≈301.59
Therefore the answer is
4 cm
I hope this has satisfied you.