A certain oilfield will be explored with license. It is anticipated that it to contain STOIIP of $5000MM$ stb$,$ and it has recovery by primary methods, secondary and tertiary methods are $25\%,20\%,$ and $15\%$ respectively. Determine the reserves and recovery by each methods. If there are a $90\%$ chance of producing at least $100MMstb,50\%$ chance of producing $500$ MM stb and $10\%$ chance of producing $700MM$ stb by tertiary, secondary and primary methods, then determine proved, probable and possible reserves.

$($This question is from petroleum engineering$)$