Question: what are the system requirements for mac os sierra?
Answer: iMac: Late 2009 or newer., MacBook and MacBook 12-inch: Late 2009 or newer., MacBook Pro: Mid 2010 or newer., MacBook Air: Late 2010 or newer., Mac Mini: Mid 2010 or newer., Mac Pro: Mid 2010 or newer., Xserve is no longer compatible.