WBCS (Executive) 2020 Prelims Previous Year Paper

The National Institute of Disaster Management (NIDM) was established in 2006. Which of the following statements is correct regarding this?

In writing the integers from 10 to 100, how many times is the digit 7 used?

When was the first battle of Tarain fought?

Potassium permanganate (${\text{KMnO}}_4$) is used to purify drinking water because it is an effective ____________ agent.

The Indian-made typhoid conjugate vaccine (TCV), approved by the WHO, was first introduced into the public health system of which country?