A method of timing accurate to millionths of a second is needed to find the distance of objects.
A method of timing accurate to millionths of a second is needed to find the distance of objects.
为求出物体的距离，需要一种精确到误差不出百万分之一秒的测时方法。
A method of timing accurate to millionths of a second is needed to find the distance of objects.
为求出物体的距离，需要一种精确到误差不出百万分之一秒的测时方法。