Final answer:
If the market price of hammers increased from $7 to $11, only Bob's Hardware would still lose surplus.
Step-by-step explanation:
In this scenario, if the market price of hammers increased from $7 to $11, only Bob's Hardware would still lose surplus. Both House Depot and Lace Hardware would still be able to generate surplus as they can offer the hammer at a lower cost than the market price. Bob's Hardware, being an independent hardware store, has a higher minimum price and would lose surplus if the market price increased.