求:; f7 }& b4 f3 ?% F$ E I
1.AB之垂直距离为何? # t7 o! I0 E4 q a.19.5606 b. 19.6506 c. 19.6605; C& `/ F6 ]" _
2.∠ABC之角度为何? / x: L, P- Z& D6 x a. 51.589° b. 51.895° c. 51.985°2 D2 T+ E4 b8 {0 K; }+ b! c3 I
3. 红色剖面线区之面积为何? $ s4 [0 f- h4 w8 }0 y$ y5 G% H a. 108.5891 b. 108.8519 c. 108.9815: `2 c. W" ?( k7 V# {# j
4. 绿色剖面线区之周长为何? 9 r8 r1 t8 a) C- m$ B# E a. 100.4837 b. 100.8473 c. 100.7384