O is reviewing the selling price of one of its products. The current price of the product is 45 per unit and annual demand is forecasted to be 130,000 units at the price. Market research shows that the level of demand would be affected by any change in the selling price. Detailed analysis of this research shows that for every 1 increase in selling price, annual demand would be reduced by 10,000 units and that for every 1 decrease in selling price, annual demand would increase by 10,000 units. A forecast of the cost that would be incurred by O in respect to this product at different activity levels is as follows: OI seeks your help in determining the optimum selling price to maximize profits. Explain the effect on the optimal price and quantity sold of independent changes to: i) The direct material cost per unit. ii) The annual fixed overhead