Which of the following is not harmed by acid rain?

concrete buildings
glass windows
marble statues
iron railroad tracks

glass windows

Explanation:

An acid rain is appears when the sulfur oxide and nitrous oxide present in the atmosphere get mixed with the water vapors forms sulphuric acid and nitric acid in the atmosphere which comes down in the biosphere in the form of precipitation called as acid rain. The acid rain is capable of causing damage to the building materials such as concrete, marble, cement also capable of causing corrosion of the iron.

The acid rain has no effect over the glass windows because of the fact that glass is a solid hard material which cannot be damaged by the any kind of chemical such as acids or alkalies.

it is the most commonly accepted one