(2014?Changzhou) Argentine scientists have designed a "cow fart collector", which is a plastic bag on the back of a cow, and collects the heat released from the cow's body through a catheter.

Q release=m1q=0.21kg×5.6×107J/kg=1.176×107J,

(2) From the question, Q suction=Q release=1.176×107J,

∵ Q suction=cm(t-t0),

∴m=

Answer: If all the heat given off by the complete combustion of this methane is absorbed by the water, it can cause 56kg of water to rise from 20℃ to 70℃. to 70°C.