1. Which is biggest planet ?

Answer: Jupiter

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 longest river in world ?

Answer: Nile, Africa

4. Which is largest continent ?

Answer: Asia

5. What is the name of tallest Animal ?

Answer: Giraffe

6. Which is the lightest gas ?

Answer: Hydrogen

7. Which is the longest rail tunnel in India ?

Answer: Pir Panjal (J&k, 11215 metre)