araef logistics P/L manufacturers parts of aviation engine and these parts are made in batches.everytime a new batch is started it costs $1640 in production and lost production of$280 in wages for fitters.one item has an annual demand of 1250units with selling price of $300, 60% of which is direct material and production cost.The corporation looks for return of 20% a year on capital..1)calculate optimal order size. 2)calculate optimal time between orders 3)calculate optimal variable cost. 4)calculate total cost