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 the highest Plateau ?

Answer: Pamir, Tibet

3. Which is the lightest metal ?

Answer: Lithium

4. Which state is largest by Population ?

Answer: Uttar Pradesh

5. Which is smallest continent of world ?

Answer: Australia

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

Answer: Rajasthan

7. Which is the brightest planet ?

Answer: Venus