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1、 )1( ) 6( ) ( ) -(2( ) 6( ) ( )7( )3 ( ) 4 ( 12 ) 56 ( . 437 2. ) ( 12 ) 72 ( .6 6 6 ? . 6 . = = = = = = = = = = + + + + + = + + + + + )= + + + + + ( )= ( 2+) ( 2)+ ( 2)= + + ( 2 = = = = = = . = + + + + + = 6)= (6 6 .)= ( 2+) ( 2)+ ( 2)= + + ( 2 )= (6 0.352 + 0.282 + 0.22 =0.7 + 0.56 + 0. 4 (m2) ) (
2、 )0.7( ) 0.5( ) 0.35 ( )0.7( ) 0.4( ) 0.28 ( )0.5( ) 0.4( ) 0.2 ( : 1.66 .()()2 + ()() 2 + ()() 2 =0.7 + 0.56 + 0. 4 (m2) =0.352 + 0.282 + 0.22 ) ( .: 1.66 .()()2 + ()() 2 + ()() 2 =0.352 + 0.282 + 0.22 =0.7 + 0.56 + 0. 4 ()()2 + ()() 2 + ()() 2 =0.352 + 0.282 + 0.22 (m2) =0.7 + 0.56 + 0. 4 ()()2 +
3、()() 2 + ()() 2 =0.352 + 0.282 + 0.22 (m2) =0.7 + 0.56 + 0. 4 =0.352 + 0.282 + 0.22 (m2) =0.7 + 0.56 + 0. 4 ()()2 + ()() 2 + ()() 2 =0.352 + 0.282 + 0.22 (m2) =0.7 + 0.56 + 0. 4 _= _(dm2)1.21.26 8.64 : 1.66 . 1.2 1 . - 4 3 2. 2. 1.5 .- . 0.750.52+0.751.62+0.51.62 0.750.52+0.751.62+0.51.62 =0.75 + 2.4 + 1.6 =0.75 + 2.4 + 1.6 ( m2 ) 0.75 0.5 1.6 )( : 4.75 . 3 3 6 3 3= 54 9 = 45(dmdm2 2) 3. ) (: 45 . 862 + 462 + 842= 96 + 48 + 64 = 208 () 2086 8() 3. 864 . 22.4 : 137.6 15cm5cm10cm 17- .