1. Who invented Safety Pin ?

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

2. Who invented Gramophone ?

Answer:

Emile Berliner in 1887.

3. Who invented Periodic table ?

Answer:

Dmitri Mendeleev invented Periodic Table

4. Who invented Helicopter ?

Answer:

Igor Sikorsky

5. Who invented Chemotherapy ?

Answer: Paracelsus of Switzerland

6. Who invented Bacteria ?

Answer: Leeuwenhock of Netherlands in 1683

7. Who invented Floppy disk ?

Answer: IBM in 1970