1. Which is smallest planet ?

Answer: Mercury

2. 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.

3. Which is the biggest museum in the world ?

Answer: British Museum, London

4. Which is the lightest gas ?

Answer: Hydrogen

5. Which is the highest waterfall in the world ?

Answer: Angel, Venezuela

6. Which is the largest Mosque in World ?

Answer: Masjid al Haram (Saudi Arabia)

7. Which is Largest railway route in India ?

Answer: Dibrugarh in Assam to Kannyakumari in Tamil Nadu.