1. Who invented watch ?

Answer:

Peter Henlein invented the first portable time piece in 1504

2. Who invented Submarine ?

Answer:

John Philip Holland

3. Who invented Logarithms ?

Answer:

John Napier (Scotland) invented Logarithm

4. Who invented X-ray ?

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

5. Who invented Printing Press ?

Answer:

Johannes Gutenberg

6. Who invented HIV ?

Answer:

7. Who invented Radar ?

Answer:

Sir Robert Watson-Watt