29-1. 8 9TU54V.\r 1 2 \r1 4 .\r, :1W=1000XRY?,\r3.14x (1.2^2 ) 2 x20x50\r=3.14x0.36x20x50\r=1.1304x20x50\r=1130.4 ( [ \ )\r1130.4^ _ ` 1000a Y ? ,\r3 0 -1 .8 95bcdeB\r, :800^=80000®* , 800004.40000=2(®*);\r1000*=100000Y ? '1000004-40000=2.501*);\rfghi9\rj k 2 5X -4-\r 0\r@ P ` 1 : 40000\r3 1 -1 ,8 TEBl >mnE2Y??2.5JS?.\r31-2\r, : 800*=80000Y ? ?@ o : 4 T 80000=1T 20000.\r3 1 -3 ,8 9p!q QrS3 @P`EL20000.\r, : 66+2=33(cm), 33* s =12(cm), 33x =21(cm)\r32-1?8 9tRu t12Y?.vE21a?.\r 1 3 \r1 4 .\r2 :3000x2.25%xlx (1 -2 0 % ),\r=3000x0.0225*1x0.8 ,\r= 54(x ) \r33-1?8 9yz{|}~ E54x.\r 1 4 \r1 4
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