When did oxygen levels start to decline from 35 percent down to today’s levels

100 percent

Explanation:

the oxgyn level todays level is 95

The oxygen levels started to decline from 35 percent down to today’s levels in 1995.

on this day in 1833, president andrew jackson announces that the government will no longer use the second bank of the united states, the country's national bank. a national bank had first been created by george washington and alexander hamilton in 1791 to serve as a central repository for federal fund