1. Who invented Aeroplane

Answer: Orville & Wilbur Wright in 1903

2. Who invented Barometer ?

Answer: Evangelista Torricelli of Italy in 1644

3. Who invented Helicopter ?

Answer:

Igor Sikorsky

4. Who invented HIV ?

Answer:

5. Who invented Safety Pin ?

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

6. Who invented Steam Engine (Piston)

Answer: Thomas Newcomen of Britain in 1712

7. Who invented Machine Gun ?

Answer:

Helge Palmcrantz, Swedish inventor and industrialist