Please I need help with solving question 4

Single Source Monkoffee is further considering to source coffee beans only from Indonesia for both medium and dark roast coffees - Use same coffee beans from Indonesia but separately roast for medium roast and dark roast Fixed order cost is $200 Inventory replenishment lead time is 4 weeks from Indonesia Operation Weekly demands (independent) (D and op) - Medium roast coffee (P1): 100 bags per week with standard deviation of 40 bags per week Dark roast coffee (P2) : 25 bags per week with standard deviation of 10 bags per week Inventory holding (H) - $40 per bag per year (10% of product cost/price) Monkoffee uses continuous review policy - Lot size (0) to replenish coffee beans from Indonesia is calculated using economic order quantity (EOQ) Cycle service level (CSL) - 0.99 Inventory-replenishment lead time (L and s) - 4 weeks Fixed order cost (5) $200 per order Calculate following for raw coffee beans from Indonesia (at R1) for the single-source operation - (3-1) Lot size (Q) From supplier to roasting facility -(3-2) Safety inventory (ss) Safety inventory of raw coffee beans at roasting facility (3-3) Annual ordering cost -(3-4) Annual holding cost - Question 4 (4-1) Calculate a total of annual ordering cost and annual holding cost for the above three cases - Current (Question 1) Two suppliers delivering independently - Joint ordering (Question 2) Two suppliers delivering jointly - Single source (Question 3) Single supplier (4-2) Based on the above calculations, what should Monkoffee do (current, joint ordering, or single source)