Which one of the following pair is mismatched? 

Which among the following is not a conservation reserve?

Which river carries water in Udaisagar lake? 

$${\sqrt{4×?}}={160\over 10}$$

$$\left({?-0.5\over 0.2} \right)={120\over 2}$$

A task force has been constituted by the Center to monitor the situation of which virus in the country.

A started a business by investing Rs. 50,000. After 6 months B joined him by investing Rs. 75,000. After another 6 months C joined with Rs. 1,25,000. What is the ratio of profit shared after 2 years among A, B and C?

In 64 liter of pure milk, 20 liter of water is mixed and then $$ {1\over 4}{th}$$ of the mixture is taken out. When x liter of water is added again then ratio of water to that of the milk becomes 1:2. Find value of x?