In chapter 6 How does Buck prove his love and loyalty to Thornton. How does Thornton demonstrate his love and respect for Buck

When John falls into the rapids of a river, Buck aids Hans and Pete in rescuing him and breaks three ribs. Later that winter in Dawson, Buck wins a $1600 bet for his master by pulling a sled loaded with a thousand pounds of flour. Buck is famous all over the region. A man offers $1200 for Buck but Thornton refuses.