To determine the total number of units of pollution that firms would eliminate based on a government fee of $93 per unit of pollution, we would need more information. Specifically, we would need to know the relationship between the fee and the firms' behavior in reducing pollution.
If the fee is designed as a penalty for pollution and the firms are motivated to minimize costs, they would seek to reduce pollution until the cost of eliminating an additional unit of pollution becomes equal to or greater than the fee per unit.
For example, if the cost of reducing pollution for a firm is $80 per unit, they would be motivated to reduce pollution until the cost of reducing one more unit is higher than the fee of $93. In this case, the firm would eliminate as many units of pollution as possible until the marginal cost of reducing pollution equals or exceeds $93.
However, without more specific information on the relationship between the fee and the firms' cost structure for reducing pollution, it is not possible to determine the exact number of units of pollution that would be eliminated.