下面是轴测图的是（ ）。 A: <img src="http://image.zhihuishu.com/testzhs/onlineexam/ueditor/201702/748c4269a50a4aa2bfab8b91fd4f0a48.png" /> B: <img src="http://image.zhihuishu.com/testzhs/onlineexam/ueditor/201702/fd1616f4949a4f5dbe2d263f38f5bbf6.png" /> C: <img src="http://image.zhihuishu.com/testzhs/onlineexam/ueditor/201702/d6dae74b734542a99835980a703c3222.png" /> D: <img src="http://image.zhihuishu.com/testzhs/onlineexam/ueditor/201702/9c9af01bbf134f52be1439f428bb093a.png" />

http://image.zhihuishu.com/testzhs/onlineexam/ueditor/201702/2bc9910080034d508f91d9a5360560ea.png

下图属于如下哪一类设计原则？http://image.zhihuishu.com/testzhs/onlineexam/ueditor/201702/c88ff0fc99894ff689b77b489e426436.png

在各国文化中对下图手势解读有哪几种？http://image.zhihuishu.com/testzhs/onlineexam/ueditor/201702/1271420236ef44e5b826fa7de4d46d86.png

在图示轮系中，根据齿轮1 的转动方向，蜗轮4 的转动方向为逆时针。http://image.zhihuishu.com/testzhs/onlineexam/ueditor/201702/280b268c577841dc806f6b55ccaf3c7f.png

在图示轮系中,已知z1=z3=z4=z6=z8=20,z2=z5=40,z7=z9=80，i19= 。http://image.zhihuishu.com/testzhs/onlineexam/ueditor/201702/99094f135fcc46388817ee5a288e9003.png

一棵m阶B-树中，所有非根节点非叶子结点中的关键字的个数必须大于或等于()http://image.zhihuishu.com/testzhs/onlineexam/ueditor/201702/3a840e57fa5d4aea98f8229aa0f31c1a.png

图 1 椭圆的半长轴 OA=3 ，半短轴 OB=2 。将图 1 中每点的横坐标不变 , 纵坐标乘同一个常数，将图 1 的椭圆变成图 2 的圆。 椭圆内接四边形 ABCD 变成圆内接正方形。则圆内接正方形面积和椭圆内接四边形 ABCD 面积分别为http://image.zhihuishu.com/testzhs/onlineexam/ueditor/201702/c33823e08fbe4e69bb7230b0a109dc55.png