Solution:

1. The International System of Units is the modern form of the metric system, and is the
   most widely used system of measurement.
   
   2.It comprises a coherent system of units of measurement built on seven base units,
   which are the second, metre, kilogram, ampere, kelvin, mole, candela, and a set of twenty prefixes to the unit names and unit
   symbols that may be used when specifying multiples and fractions of the units.
   
   3.The system also specifies names for 22 derived units, such as lumen and watt, for
   other common physical quantities.