?????¥????????′????????a?oo???è?????????′???????????????ˉ??¥???
??3??°è??é??????????????è§????????§?è?¤??????????????????è§???1?o????
?¤?é?¢?¤???°è???1??1?????oo???è??é?£?1?é???????o????1?è|????è?a?·±??????????????a?oo????????¢???
???????o??1???????é??????-|?????¨?????a?2??????¥?ˉ??????°??1???
è????????????¤??????°é£??¤??1????è???oo?¤′???????°???o?1???????????°????
???????1′????-£????¤′?°±è?????è§??????????è?±?????????????·2?????3???èμ·????¤??????·?-????
?????|??????é????-????-|??¥?1??·?????????????????2??2???|?¥1?????????è?????
?¥1??????é?′?????°?o??????????
èˉ′?????????è?1?????′???????o?????-|é?¢è·ˉé?£?1??¤??¤§?-|????????¨??a?¤§?-|??°è°???????è°??o??¥??????μ???
????¤??????ˉ???????ooé?′??????é??????????·?-????
???????è·?????????¨??-???é?£?§?é????·?-|é??è??????????¨??????????????′????o??????a?oo???
????è|???ˉ???è§???°?????°è??é???????¢è?¤??????
????2?èˉ′èˉ????
?2??2??????a??2??2?¥1??????è?2?2????èˉ?é¢????????-|????1??2??????????
????????¨????±?è?1è·¨?1′??????è??????????????????2??2?è?????è????????
è????????????????°???è????ˉ????????????è???o?è·?????????3????????????
??¨????1??????-???????oo???é????????é??è????-?1′?????????????????????é????????????????3???
???????????????è?a?·±??ˉ?????????????o????
?¤§?-|????????a?ˉ???????????????μ????|?????′§???
è?????èˉ?????????????é?′??2????o???????
??ˉ????2???3??°??????????±????è·???????????|????èμ·?????¥??o??o??¥????o????
17
é?????????1′??????è§???°?????????????????????é??????°????
?????′??|?o????????o??¤′??????????????·?-?è??è·???????é?£??·?¥???????