1. Who invented Submarine ?

Answer:

John Philip Holland

2. Who invented Stethoscope ?

Answer: Laennec of French in 1819.

3. Who invented Relativity Theory ?

Answer: Einstein of Germany in 1905.

4. Who invented Open Heart Surgery ?

Answer:

Dr. Daniel Hale Williams

5. Who invented Steam Engine (Piston)

Answer: Thomas Newcomen of Britain in 1712

6. Who invented Periodic table ?

Answer:

Dmitri Mendeleev invented Periodic Table

7. Who invented Atomic numbers ?

Answer: Moseley of Britain in 1913