The total cost of food that the cow ate for the forty days is 40*$20 = $<<40*20=800>>800
To feed and maintain the health of the cow, the total expenses Jett used is $500+$800 = $<<500+800=1300>>1300
With the expenses, Jett used $1300+$600 = $<<1300+600=1900>>1900 on the cow.
If he sold the cow at $2500, Jett made a profit of $2500-$1900 = $<<2500-1900=600>>600
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