?? �?????�????????????? ???????

????:1?????:??????
2???????
3?????????
4??????
5????????
??2??????18?????? (??????? ??????????)??�????????????????�(�????2�)18?????
�??2�?�???�?????,??????,????????????,??????????????????????,????,????????????????????�??�,?????????????�??�?????????18???????,??(?????)???123??,??????????????????21????

?????????,????????????,�??????2�?????????,??????????????,???,???,???????????�?????????????????????????????�?
??,�?????????????�?????,?????????�????????????????2�?,??,????
�???2�?????????,?�???��?????????�??,????????,?�?????????????????????????�??,???�????�???????��?????
???????,????�??�(????????????,???????�??????????????????�)??????,??????,????????????????,???�???????????�??????????????2�???�
???????????????????,�??�???????,????,????????????,?????�1+1>2�???
�?????2�????????????????????,?????????????????2??22????????????????????(????)
??????:?????