Price Variance. Definition: Price variance is the actual unit cost of a purchased item, minus its standard cost, multiplied by the quantity of actual units purchased. The price variance formula is: (Actual cost incurred-standard cost) x Actual quantity of units purchased. = Price variance. If the actual cost incurred is lower than the standard cost, this is considered a favorable price variance.
Calcium carbonate is a common, naturally occurring calcium salt that is often used as a source of calcium in supplements. Its abundance in nature makes calcium carbonate the least expensive supplemental calcium salt. It is also a major component of some types of stone that are used in architecture and sculpture.
Magnesium occurs naturally only in combination with other elements, where it invariably has a +2 oxidation state. The free element (metal) can be produced artificially, and is highly reactive (though in the atmosphere, it is soon coated in a thin layer of oxide that partly inhibits reactivity â see passivation).