Answer:
B) $7
Step-by-step explanation:
The computation of the consumer surplus is shown below:
Consumer surplus = Willing to pay - Market price
For Austin, The consumer surplus = $10 - $6 = $4
For Erin, The consumer surplus = $9 - $6 = $3
So, the total consumer surplus = $4 + $3 = $7
Simply we deduct the market price from the willing to pay so that the consumer surplus can be computed