Robinson expects its 2021 sales and cost of goods sold to grow by 5 percent over their 2020 levels.  

a) What will be the effect on its levels of receivables, inventories, and payments if the components of its cash conversion cycle remain at their 2020 levels? What will be its net investment in working capital?

b) What will be the impact on its net investment in working capital in 2021 if Robinson is able to reduce its collection period by 5 days, its inventory period by 6 days, and increase its payment period by 2 day?