(60 pts) Demand for tablets at Tech Inc. is 9,000 per month. The annual holding cost at Tech Inc. is 15 percent and the company incurred a fixed cost of $8,000 for each order placed. a. The supplier offers an all unit quantity discount with a price of $160 per phone for all orders under 10,000, a price of $155 for all orders of 10,000 or more but under 15,000 and a price of $150 for all orders of 15,000 or more. How many phones should Tech Inc. order per replenishment? Please show your computations clearly for full credit b. If the supplier offers a marginal unit quantity discount with a price of $160 per phone for less than 10,000 phones in an order, a price of $155 for more than or equal to 10,000 and less than 15,000 phones in the order, and a price of $150 for the quantity of 15,000 and above in the order. How many phones should Tech Inc. order per replenishment? Please show your computations clearly for full credit