The warm Peruvian current that appears every $5$ to $8$ years off the coast of South America in the eastern Pacific is known as:

Soil erosion is greater when

The concentration of an insecticide in the animals of a species is called:

The limit of $BOD$ prescribed by the Central Pollution Control Board $(CPCB)$ for the discharge of industrial and municipal wastewater into natural surface waters is

When was the Bharat Stage $IV$ emission standard implemented for vehicles in the city?

Polyblend is mixed with $\underline {i}$ and is used to lay $\underline {ii}$.