????

?? ??????????????????????????????1.???????????????????2.????3?????3????????????????????????3.?? a.?????????0.252?????12(?????????)b.????????????????????????????????????????4.? a.????1030??4???b.??????460.1???0.5?0.5??????0.5?0.25?0.5?(0.5)o??c.??????15?0.30.5??B(2)0.250.5?0.5??d.????????????????1?1??????????1???????????????e.?0.1???(25000)0.1?0.5?0.5???5.?:a. ????????????????b.????(Buller)??????????????????????