) 2 X3.14X 1 -20xl0x 1 =57 ( cm2 )\r26-1 2 2\r:?@AB=BC ,\rABS“ BD=21,21+ (6+2 ) 23.14X 1 =35.13 ( cm2 )\r26-2 2\r@: BC=12cm , BO=OC=6 ( cm )\rS“ BC=2X10=20 ( cm2 )\rSffi= 4 x62 x3.14-20= 36.52 ( cm2 )\r26-3 2\r%&1$'7\r%&2$'6\r%&3$'7\r%&4$'2\r%& C '12\r%&6$'11\r%&7$'3\r27-1 %&8$'9\r4x50+50\r=200+50\r=4 ( DE)\r27-25 6G : ?\ryb z8z{5|}~e0(F22" ) ( F 4 ekF 22")\rD 1 3 E F 1 4 E.\rt?: 105x11=1155 (=F*)\r1155 K <1255^K\r28-15 611DELMNOPQRP.\r29-1TU,VW:,UVXY30°; 60° ; 90°\r2145+(1-2.5%) = 2200(A)\r30-E 5 62017Z[\]D^_2200`.\ra 6bcdefE7ghij;.\r5.0%xx3+x=92000\r1.15x=92000\rx=80000\r31-15 6ckfE7ghi80000l.\rD 1 4 E F 1 4 E
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