If a meter stick has a mark every 10 cm (100 mm) the least count is 10 cm. If marked off in centimeters the least count is 1 cm. If marked in millimeters the least count is 1 mm. In this experiment we will use some instruments with least counts of 0.1 mm and 0.01 mm. It is often possible to estimate a measurement to some fraction of the least count. The smallest fraction to which you can reliably estimate is called the instrumental limit of error (ILE). All measurements should be made to the ILE of the instrument. Suppose you have a clock with sixty divisions on its face. The least count of the second hand is _______________ ? The least count of the minute hand is _______________ ? The least count of the hour hand is _______________ . Look carefully at the face of a clock and you will see that the correct answer is not "one hour".