How do I find the protons neutrons and electrons for and Oxygen Ion with an oxidation charge of -2

Asample of radium-226 will decay 1/4 of its original amount after 3200years. what is the half-life of radium-226?

If a solution is considered basic, then a) the hydroxide ion and hydronium ion concentrations are equal. b) the hydroxide ion concentration is less than the hydronium ion concentration. c) the hydronium ion concentration is greater than the hydroxide ion concentration. d) the hydroxide ion concentration is greater than the hydronium ion concentration.

How have the greenhouse gasses increased from the year 2000 to 2018