. If you know that the cost of total production at the beginning of the period is 40,000 riyals (of which 30,000 riyals are variable), the number of units produced during the period is 16000 units, the number of units of total production at the end of the period is 5100 units, the cost of one unit of total production is 7 riyals according to the variable cost method, total industrial costs Sold units