How can producers make the most profit? check all that apply?

I believe to make the most the producers can implement the following; 
They can work to decrease their marginal cost, they can raise prices to increase marginal revenue, they can also keep the marginal cost below marginal revenues. The producers are the suppliers of various goods and services in the market according to the demand of the consumers. They determine the amount of goods in the markets.

The atmosphere wasn’t strong enough to contain more oxygen when compared earths atmosphere today, the exosphere was full of rips and couldn’t contain enough oxygen to provide for land creatures, although aquatic earthlings could continue i exist in this environment