List of top Air and Noise Pollution Questions on Air quality indices visibility asked in GATE ES

The sub index values of NO$_2$, SO$_2$ and PM$_{10}$ are 80, 80 and 100, respectively. According to the National Air Quality Index (NAQI) released by the Government of India in the year 2015, the overall NAQI is:

Consider the figure shown below for three different cases. Which of the following statement(s) is/are correct for surface level emissions, given the environmental temperature?

A bag filter is used for removal of particulate matter having a range of sizes. The correct sequence of air filtration mechanisms for their removal, in order of decreasing size, is