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%.
Gross profit margin. Gross profit margin is gross profit expressed as a percentage of sales. Use this formula to calculate your gross profit margin.our gross profit margin is a key indicator of your business's overall health. The gross profit margin shows whether the average mark up on your products or services is enough to cover your direct expenses and make a profit.