1. Who invented Calculus ?

Answer: Newton of Britain in 1670.

2. Who invented Computer ?

Answer:

Charles Babbage

3. Who invented Chloroform as anaesthetic ?

Answer: James Simpson of Britain in 1847.

4. Who invented Stainless Steel ?

Answer: Harry Brearley of Britain in 1913.

5. Who invented paper ?

Answer:

Cai Lun

6. Who invented Safety razor ?

Answer: King Camp Gillette of U.S.A. in 1903

7. Who invented X-ray ?

Answer: W.K. Roentgen of Germany in 1895.