Hi, please help calculate 3.1 and with the productivity ratio do I convert it into a percentage or not

Question 2 [20 Marks] You are provided with the following information. Conduct an ABC analysis, categorising each item of stock appropriately. (80% = A, 15% = B, 5%=C) Item no. Unit cost (R) Annual Demand 5 101 102 103 104 105 106 107 108 109 110 48 000 2000 300 800 4800 1200 18000 300 5000 500 9 12 Question 3 (15 marks] Hingston Mansingh, a manufacturing company, has done exceptionally well with productivity, efficiency and percent value-added time ratios being consistently over 80% for the previous three years. This year, total output and input measured R10 200 000 and R10 250 000 respectively. The two production managers of the company. Ndlovu and Naidoo both had targets for the year; each director is expected to achieve 40 completed units an hour. Manager Ndlovu's team in producing Samsing laptop bags achieved an output of 37 units per hour while Manager Naidoo's team, manufacturing Appol laptop bags, achieved an output of 41 units per hour. It was noticed the customer service division should take 10 minutes to deal with customer queries, yet, customer services normally spent 25 minutes on this function. You are required to: 3.1. Calculate the productivity ratio and comment on the performance of Hingston Mansingh. (5 marks) 3.2. Calculate the efficiency of each of the managers and comment on their performance. (5 marks) 3.3. Calculate the percent value added time of the Customer Service department and comment accordingly