In a distance time graph, when the x and y values are positive (in first quadrant), the runner is moving forward.
While, if the distance value ( in the y axis) is negative, the runner is moving backwards ( towards the start) .
Hope it helps :)
You have to find the calculate<span> the circumference first then you can just multiply the diameter by π, which is about 3.142. That gives you the distance for each </span>revolution<span>. Then you can multiply by the </span>number of revolutions<span> per minute.
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Light because they need light to grow
The air would contract therefore the answer is the second choice.