Identify the correct statement from the following: . Done In piece wage system all workers are paid high rate In piece wage system workers are not motivated Under time wage system the earning of all the workers are same None of these Which one of the following is the correct formula to calculate contribution under marginal costing? Done None of these Sales - direct material - direct labor - variable factory overheads- variable selling... Sales - direct material - direct labor - fixed factory overheads Sales - indirect material - indirect labor - variable factory overheads - fixed factory overhe.. Which one of the followings correctly describes the calculation of prime cost? Done Prime cost = indirect material + direct labor + direct expense Prime cost = direct material + direct labor + direct expense Prime cost = indirect material + indirect labor + indirect expenses Prime cost = direct material +indirect labor + direct expense