1. Which is the brightest planet ?

Answer: Venus

2. Which is largest Delta of India ?

Answer: Sundarban (W. Bengal)

3. Which is the lightest gas ?

Answer: Hydrogen

4. Which is longest river in world ?

Answer: Nile, Africa

5. Which is longest railway station ?

Answer: Grand Central Terminal, Chicago(USA).

6. Which is highest dam in world ?

Answer:

Jinping-I Dam - 305 m (1,001 ft) in China on Yalong river.
Second Highest is Nurek Dam 300 m (980 ft) Tajikistan on Vakhsh river.

7. What is the name of brightest star ?

Answer: Sirius