1. Who invented Submarine ?

Answer:

John Philip Holland

2. Who invented Vitamin D ?

Answer:

Edward Mellanby discovered Vitamin D while researching a disease called rickets in 1922

3. Who invented Vitamin K ?

Answer: Doisy Dam of U.S.A. in 1938.

4. Who invented Safety Pin ?

Answer: Walter Hunt of U.S.A. in 1849

5. Who invented Piano ?

Answer:

Bartolomeo Cristofori

6. Who invented DNA Structure ?

Answer: Crick(UK), Waston(US), Wilkins(UK) in 1951

7. Who invented Chloroform as anaesthetic ?

Answer: James Simpson of Britain in 1847.