Assume a heifer enters the feedlot weighing 650lbs and leaves weighing 1250lbs. The heifer was on feed for 150 days. On average, she ate 20lbs of dry feed per day. What was the heifer's average daily gain (ADG)?
a) 4 lbs/day
b) 6 lbs/day
c) 8 lbs/day
d) 10 lbs/day