The beginning of the amazing events at Krakatoa in 1883 date to May 20 when there were initial rumblings and venting from the volcano, which had been dormant for about 200 years.
A refinery margin is the revenue associated with refining petroleum, expressed as a value per volume (e.g. $/L), net of the cost of the crude oil input. The simplest refining
In general, it is defined as the ratio of profits earned to total sales receipts (or costs) over some defined period. The profit margin is a measure of the amount of profit accruing to a firm from the sale of a product or service.