Question

If a graph was drawn to show the speed of a car, what would the slope look like as a car is sitting at a red light?

positive

negative

zero

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Answer 1

if you are sitting at a red light, then presumably you are not moving. slope would be zero

Answer 2

actually that is a rather bad explanation. the reason the slope is zero is because you are at a constant speed, not because your speed i zero.
the slope would also be zero if you had the cruise control set at 65 mph and went at exactly that rate for a while