1 The presence of a substance and the amount of that substance. 2  Thus, an assay may be done for example to determine the level of thyroid hormones in the blood of a person suspected of being hypothyroid (or hyperthyroid). 3  The biological or pharmacological potency of a drug. Thus, an assay may be done for example to determine the level of thyroid hormones in the blood of a person suspected of being hypothyroid (or hyperthyroid). 2  The biological or pharmacological potency of a drug. 3  For example, an assay may be done of a vaccine to determine its potency.
The total cost curve graphically represents the relation between total cost and the quantity of production. This curve can be derived in two ways. One is to plot a schedule of numbers relating output quantity and total cost. The other is to vertically add the total variable cost curve and the total fixed cost curve.he total cost curve is frequently used with a total revenue curve to determine the profit maximizing level of production for a firm. However, this curve is perhaps most important as the basis for deriving the average total cost curve and the marginal cost curve.
â¢ The total costs line is a representation of the combined variable and fixed costs. increases the total cost line varies with it and in parallel with the variable cost line. when the budget or actual sales is compared to the break even level of sales. losses at different levels of sales volume achieved.