I think you mean "milliseconds". The prefix "milli" is used in the metric system of measurements to mean "one thousandth of", so a "millisecond" is one thousandth of a second, which means that there must be 1000 of them in 1 second.
100
100
The second word of many limericks is typically "was."
How many men was in the second bull run?
Saturn is the second largest planet with many rings.
1000
1000
1,000,000,000,000
0.042 second
1,000,000,000 = 1 second
100 hectoseconds in a second
0.72ns