The method of solving the sixth problem in the synchronous guidance of primary school mathematics volume 1 3 1 page
1 year =365 days =8760 hours 8760 times 2.5 = 2 1 900 (kg)1t =1000 divided by1000 = 21.9. ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! That's about it. Why don't you take a look at it yourself and rate it as the best ok?