Question: 1 second means how much nanosecond?
Answer: A nanosecond (ns) is an SI unit of time equal to one billionth of a second, that is, ​1⁄1 000 000 000 of a second, or 10−9 seconds. The term combines the prefix nano- with the basic unit for one-sixtieth of a minute. A nanosecond is equal to 1000 picoseconds or ​1⁄1000 microsecond.