The average concentration of $CO_2$ in the atmosphere is

Polyblend is mixed with ...$A$... to lay roads in ...$B$.... Complete the given statement by choosing the appropriate option for $A$ and $B$.

Increase in concentration of a toxicant at successive trophic levels is called

Match the following and choose the correct combination from the options given:
Column $I$ | Column $II$
$(1)$ $DDT$ | $(p)$ $CO, CO_2$
$(2)$ $PAN$ | $(q)$ Smog
$(3)$ Acid rain | $(r)$ Biological magnification
$(4)$ Global warming | $(s)$ $SO_2$

Domestic sewage mainly contains $A$ wastes which are readily decomposed with the help of $B$. Here $A$ and $B$ refer to:

$A$ plastic sack manufacturer in Bangalore found an ideal solution to the ever-increasing problem of plastic waste. Identify this person.