1. Who invented Piano ?

Answer:

Bartolomeo Cristofori

2. Who invented Calculus ?

Answer: Newton of Britain in 1670.

3. Who invented Machine Gun ?

Answer:

Helge Palmcrantz, Swedish inventor and industrialist

4. Who invented Atomic Bomb ?

Answer: J. Robert Oppenheimer of U.S.A. in 1945

5. Who invented Stainless Steel ?

Answer: Harry Brearley of Britain in 1913.

6. Who invented Radar ?

Answer:

Sir Robert Watson-Watt

7. Who invented Transformer ?

Answer:

Ottó Bláthy