1. Who invented Vitamin A ?

Answer: Mc Collum and M.Davis of U.S.A. in 1913

2. Who invented Ballistic missile ?

Answer: Wemher von Braun of Germany in 1944.

3. Who invented Machine Gun ?

Answer:

Helge Palmcrantz, Swedish inventor and industrialist

4. Who invented Submarine ?

Answer:

John Philip Holland

5. Who invented Atomic theory ?

Answer: Dalton of Britain in 1803.

6. Who invented Printing Press ?

Answer:

Johannes Gutenberg

7. Who invented Neutron ?

Answer:

JAMES CHADWICK in 1932