Instead of thinking about one field changing in response to the change of the other, it is more correct to say that. whenever the magnetic field is changing, so is the electric field, and vice versa.The way these fields change is governed by Maxwell's equations.This way, we do not arrive at the confusion OP has.nstead of thinking about one field changing in response to the change of the other, it is more correct to say that. whenever the magnetic field is changing, so is the electric field, and vice versa.
Gross profit = net sales â cost of goods sold. Gross profit percentage = [(net sales â cost of goods sold)/net sales] Ã 100%.
Understand Gross Profit Margin. The Gross Profit Margin (GPM) is the percentage of revenue a company has left over after paying direct costs of producing goods. All other expenditures (including shareholder dividends) must come out of this percentage. This makes the GPM a good indicator of profitability.