<span>The GCF is the number that is a factor of both (or all) of the numbers of a given set and which is the biggest factor of this kind (often the smaller number of the two)
7 and 14 have a greatest common factor of 7.
28 and 7 also have a GCF of 7, so the first two responses fit.
21 and 3 have a GCF of 3, so that isn't correct.
7 and 1 have a GCF of 1, so that's incorrect as well.</span>
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 
one hundred thirty two million, eight hundred eighty thousand and sixteen
(Your commas are in the incorrect spot)
fifteen thousand, eight hundred and two
Answer:
you should get 6 four-packs
Step-by-step explanation:
5.28/6= .88 dollars per roll
3.40/4=.85 dollars per roll
buying six four packs is a better price