I have the right solutions for thoses questions but i need to know how to calculate it! The bold answer is the correct one.

You are the new chief operations officer (COO} of your company, and you are analyzing the situation of your production, which is as follows:

- Your production machines are old and have an average downtime of 1 hour/day. - In addition, the machines require a new or corrected setup of the settings every 4 hours. This setup werk requires 30 min. - Unfortunately, every 8 hours a product is defective, even though you only run the machines at 90% capacity. - In the remaining productive time, the machines produce one product every 2 hours. - Currently, your production team works 8 hours/day.

a} What is the total operating time? A. 6 hrs. B. 24 hrs. C. 8 hrs. D. 5.4 hrs. E. 3.4 hrs.

b} What is the valuable operating time? A. 6 hrs. B. 24 hrs. C. 8 hrs. D. 5.4 hrs. E. 3.4 hrs.

c) What is the danger of looking at the overall equipment effectiveness (OEE) in isolation as the only metric? A. The utilization of the machines is too low. B. Production volumes are too small. C. Changeover times are too long. D. The quality is too low. E. Batch sizes are too large.