We need to raise 300 bushel per acre corn to be profitable. Do we need micros such as sulfur and zinc?
YES!!!!
Here are a few links to get you energized to raise a corn crop of 300 + bushels per acre
https://www.sulphurinstitute.org/fertilizer/
https://extension.umn.edu/micro-and-secondary-macronutrients/zinc-crop-production