If the half-time of krypton-81 is 229,00 years, how much krypton-81 was present when the ice first formed

A1 a 2 a 3 ooh lol i think that's it

It will appear as o2(g) as a reactant 

Aseasonal prevailing wind in the region of south and southeast asia, blowing from the southwest between may and september and bringing rain (the wet monsoon ), or from the northeast between october and april (the dry monsoon ).

B. nuclear reactions could first occur.