Which unit is used to measure size of a nucleus ?

The radius of the platinum atom in a nucleus is 60.2 fermi. Find the volume of the nucleus. Why fermii is used to measure size of a nucleus?

Name the unit used to measure size of a nucleus and express it in metre

The size of nucleus is

Which unit is used to measure purity of gold?

Which unit is used to measure electrical energy ? (or) Define kilo watt hour.