Selection B is appropriate.
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It takes 12 times as long to fill the whole tank as it does to fill 1/12 of the tank.
.. 12 * (1/3 hour) = (1/3)*12 hour
8 feet, because 10^{2} - 6^{2} = 64;
\sqrt{64} = 8[tex]
So what will it be a percentage of? it will be the percentage of the original recruits, of the original 150.
for this, we need to divide the number of recruits that left over all recruits, and multiply by 100%:

so the number of trainees decreased by 20 %
Going 315 km uses up 35 liters of gasoline
On average, 1 liter of gasoline can travel the number of kilometers:
315 : 35 = 9 liters of gasoline