1. 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.

2. Which is largest Delta of India ?

Answer: Sundarban (W. Bengal)

3. Which is the brightest planet ?

Answer: Venus

4. Which is Longest road tunnel in the World ?

Answer: Lærdal Tunnel (Norway - 24.51 kilometre)

5. Which is the largest Mosque in India ?

Answer: Jama Masjid (Delhi)

6. Which is longest river of India

Answer: Ganges

7. Which is the state largest by area in India ?

Answer: Rajasthan