??
?????????????????????????1?????18???(? ???)1?????18???????????,???????????????2.7??3.2??????????:???2.7???????????3.2?1???2?????4.8???????????4.6???,???,???,????????????????????
??,??,????
??,???2.7???????????????????????????????????????????????;?3.2?????????????????????????????????????(??????)????,????????????????(?) ??:????
?????????
??????????????? ????????????????????????