The cost of supervision over machines in a factory can be apportioned on the basis of: ^ Done Power used by each machine Time spent by supervisor on each m.. Floor area for each machine Idle time The amount of wages paid to production workers is an example of: Done Fixed cost Variable cost Semi-variable cost Semi-fixed cost Identify the correct statement from the following: ^ Done Marginal costing is also known as variab.. In marginal costing, fixed manufactu.. In marginal costing, fixed selling expens.. In marginal costing, the closing stock is