?-?-?У????????19?????á???????????????????????????????
????????й淶????β???????β??л??ī???ι??????
???????Ч?й?????仯???Чй????????????
???
??????
??????ε??
????????
??
?????Ρ??β?в??β????α????к?????????Ρ?л??没???
??????о????θ?á????????θ???????????ε???????????У???????????β????????顣??????????С塢???????????????
???????????????????ε??????B??ж??????Щ????
??? ?
???У????? ?λ??鶼????????Ч?Ч???????顣????????????????
????????3%~5%??????и?10%???????????
???????з????????????????ι??
????????????????С???????????μ??鼰??з??
???????Ч?????????仯緢????????




            ??