Answer:

1.Motion requires force to cause that change. The time you take to travel the distance depends upon speed; the distance travelled is measured as the length of a line between the start and end of a motion

2.We need standard unit for measurement to make our judgement more reliable and accurate. For proper dealing, measurement should be same for everybody. Thus there should be uniformity in measurement. For the sake of uniformity we need a common set of units of measurement, which are called standard units