A substance changes from liquid to gas
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Speed is defined as the distance over time. So in measuring the speed of a car, the most manual thing that we can do besides using a speedometer is to measure a certain distance then measure the time at which the car passes that distance then divide the distance over the time. Then determine the speed limit.
“We LoVeEe BiDeN bEcAuSe hIs HeAlThCaRe iSn’T FrEeEeE!”