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
Margin is a loan from your broker to help pay for the securities you buy. Normally, you can finance up to 50 percent of your purchases with margin. For example, if you have $10,000 in cash in your margin account, you can buy $20,000 worth of stock. The shares you buy are collateral for the loan of $10,000.