100\rI:UV L\nR W .0TNL?RX\nYOZ 1 .\r25-2 100\rnx 2=30x3.14=942 m2 .\r26T 0@P`p% ?2m2.\rC 1 1 D ? 1 3 D.\r8\r27-ls\r27-2!\r27-3!defghijk90° , jkopA r\nstu,7 , 1 . B r\n< 2 3 5 (7,4) , C r S W 3 S (9,4).\r { 0@P`p?? 22\n?? 4 `? 22\r0 :60/6 = 360,.\r360+5 = 72 , .\r28-1. I J h
72.\r29-1 i \r29-2! ;<1:=1J50\rC 1 2 D ? 1 3 D.\r29-3!\n@P?\r :180 x (1+20% )\r= 180x1.2\r= 216()\r30-1!I Ju216.\r0 Jx ,40-4 .\r3x-2(40-x) =30\r3x-80+2x=30\r5x=110\rx=22\r40-22=18 (A )\r3 1 -1 ,I J22 &18.\rC 1 3 D ? 1 3 D
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