Each AGS was worth 500 bts, as there were 4,000,000 AGS and 2,000,000,000 bts
Of the 4,000,000 AGS only half of them came from btc donated the other half came from PTS donated
This only answers half your question, I do not know how much in btc was raised before 2/28. That amount of btc divided by 2,000,000 x 500 would get you the average price per BTS paid by AGS investors I believe. I think it is about 1/2 of the current value of BTS.