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
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.