We are asked what is the range of market prices that would assure that the firm would produce exactly 6 generalizations. All we need to do is remember how profit maximizing behavior works. For the firm to produce exactly 6 generalizations means the price must be at least as high as the MC for the 6^th unit but not as high as the 7th. As we see below, the MC of the 6^th is $35. If the price were any lower the firm wouldn't produce a 6^th unit. The MC for the 7^th is $40 so the firm would produce 7 units if the price were $40, so the answer is between $35 and $40.

1. between $26.66 and $33.33. If the price were between $26.66 and $30 the firm would produce 4 units, if it were between $30.00 and $33.33 it would produce 5.
2. between $26.66 and $28.57. If the price were between $26.66 and $30 the firm would produce 4 units.
3. between $30 and $35. If the price were between $30 and $35 the firm would produce 5 units
4. between $35 and $40.
5. between $160 and $200. If the price were between $160 and $200 the firm would produce a hell of a lot more than 6 or even 7 units.