1. Which is Longest national highway of India ?

Answer: NH-7 ( Varanasi to Kanyakumari - 2,369 km)

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 Largest lake of the world ?

Answer: Caspian Sea (371,000 sq km)

4. Which is the longest Platform ?

Answer:

Gorakhpur railway station, Uttar Pradesh, India (1355.40 meters)

5. Which is longest river in world ?

Answer: Nile, Africa

6. Which is Largest Dome in World ?

Answer: St. Peter's Basilica (Rome)

7. Which is the largest Zoo in the World ?

Answer: Berlin Zoological Garden (Germany)