Derived units

(2): Derived Quantities:
ALL THOSE QUANTITIES WHICH CAN BE EXPRESS IN THE TERM OF BASIC QUANTITIES AS KNOWN AS DERIVED QUANTITES
MECHANISM OF Derived Quantities:
(1): BY MULTIPLICATION OF BASIC QUANTITIES
EXAMPLE: L L=AREA &L L L=VOLUME
(1): BY DIVISION OF BASIC QUANTITIES
EXAMPLE: S T=VELOCITY
(3): BY BOTH
EXAMPLE:
UNIT:
THE STANDARD WITH WHICH THINGS ARE COMPARED AS KNOWN AS UNIT
TYPES OF UNITS
(1): BASIC UNITS
(2): DERIVED UNITS
(3): SUPPLEMENTRY UNITS
(4): COMMERCIAL UNITS OR PRACTICAL UNITS