The middle point of BC is (0,2), the midpoint of CD is (1,0)
to prove two lines are parallel, prove their slopes are the same.
slope of BD: m=rise/run=4/-2=-2 (the run is negative because to get to B from D on the grid, you have to move from right to left, then upward. If the horizontal move is from left to right, the run is positive)
slope of EG: m=rise/run=2/-1=-2
EG and BD have the same slope, so they are parallel.
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