Based on the current amount that Rob makes selling sandwiches to students, his economic profit would be $20.
First, find out how much he was getting paid:
= 20 x 9
= $180
The amount he makes from selling sandwiches is:
= 300 - 100 for supplies
= $200
His economic profit is:
= Current income - Previus income
= 200 - 180
= $20
Find out more on economic profit at https://brainly.com/question/8960234.
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