He made 2 gallons and each gallon had 16 glasses so 2*16 = <<2*16=32>>32 glasses
He drank 5 glasses and had 6 left over which means he would not earn money on 5+6 = <<5+6=11>>11 glasses
The total revenue would come from 32-11 = <<32-11=21>>21 glasses
Each gallon cost $3.50 to make so the total cost was 2*3.50 = $<<2*3.50=7.00>>7.00
He sold 21 glasses at $1.00 per glass for a total of 1*21 = $<<21*1=21.00>>21.00
When you take his earnings of $21.00 and subtract the cost of $7.00 his total net profit was 21-7 = $<<21-7=14.00>>14.00
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