During the catalytic production of sulphur dioxide $,$to sulphur trioxide, $20000$ moles of sulphur dioxide and $10000$ moles of oxygen were reacted. The product stream contained $12000$ moles of sulphur trioxide, $4000$ moles of oxygen and $8000$ moles of sulphur dioxide Determine $($a$)$ the conversion of sulphur dioxide $($b$)$ the efficiency of the process with respect to sulphur dioxide $($c$)$ the yields of sulphur trioxide with respect to sulphur dioxide