There were 9 passengers on the bus because no passengers got off during the six stops and the fifth stop is within that.
D) perpendicular!
A perpendicular's definition is: a straight line at an angle of 90° to a given line, plane, or surface.
And if you mark them on a graph you could see these two are opposite of each other.
12-3.7+(1/3)=constant
259/30=constant
