Suppose a railroad rail is 3 kilometers and it expands on a hot day by 20 centimeters in length. approximately how many meters would the center of the rail rise above the ground?

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Marcus and cody both leave the park at the same time, but in opposite directions. if cody travels 6 mph faster than marcus and after 4 hours they are 64 miles apart, how fast is each traveling? solve using rare times time = distance.