There are three main sources of heat in the deep earth: (1) heat from when the planet formed and accreted, which has not yet been lost; (2) frictional heating, caused by denser core material sinking to the center of the planet; and (3) heat from the decay of radioactive elements. CROSS SECTION shows Earth's structure.
â The operating margin was an especially useful metric or ratio during the meeting as we wanted the discussion to include revenue statistics.
An operating expense is the ongoing cost of running a product, business, or system. Its counterpart, a capital expenditure, or non operating expense, is the cost of developing or providing non-consumable parts for the product or system.