以下那些操作可以新建一个背景？ A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/40aa135f5f0a475f971257bb827504fb.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/9307bb62780f4beb9816a80655aa869f.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/4c22f5c8020040beaa0fe566345b7eb9.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/e66c4f191e944062b31d06d70642aa3f.png" />

以下那些操作可以新建一个角色？ A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/be5248f5c01c40febe40711f7db7dbd8.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/bfcfceb7083741d8a0093bd21893a0f2.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/ca41a907d3b648ebb85161bf0477e47d.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/8a75d8860f284339b0d92f7c627b5c9b.png" />

以下操作，可以将数据放入列表A的是：（ ） A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/be509830d9fa481e937a24d1e2d9ad46.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/56c2e754f3684727b65b6eb649aff2fa.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/a591d719880b457ea72ff0b84b29d4e9.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/deca818437954173af522e786916847f.png" />

圆的半径为r，计算圆的面积正确的是：（ ） A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/c19fbad9b7a4479da24ef420164ea0b1.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/e7633147e3cd495fafb844f7a0098c20.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/15264e22e6824870a06d2014e4ba03f5.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/03f2b22667a84b5d83f9364a7ad27e1d.png" />

http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/919d6feb781a45b7b939ef02f334ef1e.png

关于斜弯曲的主要特征有四种答案，试判断哪一种是正确的。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/42375925fb1245cebbfabe4a5cde4d5a.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/6055f7367a0b466581761cb41cf73e10.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/a028bfcdbbcc4cb592fb6cd9d78b736a.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/6abdbfbb54644603b4269b938e091af5.png" />

空心圆轴的外径为D，内径为d, α=d/D。其抗扭截面系数为( )。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/a4529f25a3514c4fb3fb60740f65c915.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/ed201b86c65c4e91be69e526278e5396.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/997a80bcc1dd4cbd9aacbdc8724ccaf9.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/c3e0ca0958684b89bce9d01917a38b5a.png" />

电影、电视剧中常常可以看到古琴，但也存在很多错误的古琴摆放方式，以下图片中，正确的古琴摆放图片为？（ ） A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/72ff75fe949c44d796405ab3b88eda07.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/970629500bbc4f089bad19c3045e45f7.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/23f7b6b2c04048a990fcd07653bf9217.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/bed0c78e85c846e0aa005eccfe612c80.png" />

下列化合物有旋光性的是( )。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/42754375451947b4a2097a204914e285.png" border="0" vspace="0" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/259cc0f9369441888e4306c19039152f.png" border="0" vspace="0" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/c6798f5eb7e14df7a79f40cdd7d2f42e.png" border="0" vspace="0" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/4275928f484d4bad94705297fe159cf0.png" border="0" vspace="0" />

如果SSE表示多元线性回归模型的回归离差平方和，SSR表示残差平方和，SST表示总误差平方和。下面的表述哪个是正确的？ A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/73728f98836f49df97fd0e432e8dc53b.png"/> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/e9ce4f2530df450eb1d13d1563b51f1e.png"/> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/91303c4fa8324a20a46a06abe425e675.png"/> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201907/29aa50acf3a1485a8e572139e1c52c28.png"/>