99 percent of the atmosphere is made up of either oxygen or

Nitrogen

Explanation:

The Earth’s atmosphere is primarily consists of gases and rare elements.  

99% of atmosphere is composed of gases like oxygen and nitrogen. The percentage composition of earth’s atmosphere is - Nitrogen — 78 percent, Oxygen — 21 percent, Argon — 0.93 percent, Carbon dioxide — 0.04 percent also there are several rare elements such as helium, methane, argon, hydrogen, water vapour , etc.  

Thus, it can be said that 99% of atmosphere is made up of oxygen and nitrogen.

post-impressionism is a predominantly french art movement that developed roughly between 1886 and 1905, from the last impressionist exhibition to the birth of fauvism. post-impressionism emerged as a reaction against impressionists' concern for the naturalistic depiction of light and colour.

explanation:

thinking it would be physical characteristics