Read the passage carefully and choose the best answer to each question out of the four alternatives.
The problem of water pollution by pesticides can be understood only in context, as part of the world to which it belongs- the pollution of the total environment of making. The pollution entering our waterways comes from many sources, radioactive wastes from reactors, laboratories, and hospitals; fallout from nuclear explosions; domestic wastes from cities and towns; chemical wastes from factories. To these is added a new kind of fallout the chemical sprays applied to crop lands and gardens, forests and fields. Many of the chemical agents in this alarming melange initiate and augment the harmful effects of radiation, and within the group of chemicals themselves there are sinister and little- understood interactions, transformations, and summations of effect.
Even since the chemists began to manufacture substances that nature never invented, the problems of water purification have become complex and the danger to user of water has increased. As we have seen, the production of these synthetic chemicals in large volume begin in the 1940’s. It has now reached such proportion that an appalling deluge of chemical pollution is daily poured into the nation’s waterways. When inextricably mixed with domestic and other wastes discharged into the same water, these chemicals sometimes defy detection by the methods in ordinary use by purification plants. Most of them are so complex that they cannot be identified. In rivers, a really incredible variety of pollutants combine to produce deposits that sanitary engineers can only despairingly refer to as “gunk”.

The word ‘gunk’ in the last line refers:

How long has Sebi Chairman Ajay Tyagi extended for the Central Government?

Mahavir Swami was born at: 

Direction: In the following questions, out of the four alternatives, choose the one which best expresses the meaning of the given word as your answer.

ABJURE

In the triangle ABC, AB = 2 cm, BC = 3 cm and AC = 4 cm. D is the middle point of AC. If a square is constructed on the side BC, what is the area of the square?

Ramesh marks his goods 30% above cost price. If he sells the item for ₹ 910 after allowing of 15% discount. Find his cost price.

A sum becomes 5 times of itself in 3 years at compound interest (interest is compounded annually). In how many years will the sum becomes 125 times of itself?

Who has been selected for the International Anti-Corruption Champions Award by the US President Joe Biden's administration?