2. Cash turnover days = inventory turnover period (90 days)+accounts receivable (60 days)-accounts payable week (60 days) = 90 days.
Optimal cash holdings = 20 million /360 days (one year) ×90 days = 5 million.
Three (1) = (2× 4000×100/5) (1/2) = 400 kg.
(2) = 4000/400 = 10 times
(3) = 10 times × 100 yuan/time+400 * 5/2 = 2,000 yuan.
Take a good look at the rest .