They use seismographs. it measures the force and duration of an earthquake
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Plessy v. Ferguson allowed the southern states to make a doctrine that came to be know as “separate but equal”
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If you are driving 30 mph under ideal conditions , and you see a problem, you can stop in less than 100 feet. Hence, option D is correct.
<h3>What is the overall
stopping distance at 20 miles per hour?</h3>
In the 45 feet between perception and reaction, an automobile will move at 20 mph (30 feet per second x 1.5 seconds). After applying the brakes, the vehicle travels 64 feet in total, or around 19 feet, before coming to a stop.
When moving at less than 40 mph, you must maintain a minimum of one second of separation for every 10 feet your vehicle is long, according to the rule of seconds. If your speed is greater than 40 mph, add a second.
Thus, option D is correct.
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