Refer to the Following Information to Answer the Questions -If Emissions of This Pollutant Are Not Regulated, Then the Firms

Refer to the following information to answer the questions.
Two firms both emit a pollutant, and the government wants to reduce emissions of this pollutant. Each firm can choose to emit up to six units. As firms reduce emissions, there is a marginal cost per unit. This data is presented in the accompanying table. $\begin{array}{rlr}\text { Firm 1 } & \text { Firm 1 } & \text { Firm2 } & \text { Firm2 } \\\text { Emissions } & \begin{array}{l}\text { Margival } \\\text { Cost }\end{array} &\text { Emissions }& \text { Marginal Cost } \\0&\$ 60 & 0 & \$ 120 \\1&\$ 50 & 1 & \$ 100 \\2&\$ 40 & 2 & \$ 80 \\3&\$ 30 & 3 & \$ 60 \\4&\$ 20 & 4 & \$ 40 \\5&\$ 10 & 5 & \$ 20 \\6&\$ 0 & 6 & \$ 0\end{array}$
-If emissions of this pollutant are not regulated, then the total emissions from the two firms equal:

A) 12 units.
B) 6 units.
C) 0 units.
D) 10 units.
E) 9 units.