图示结构，忽略各杆件的轴向变形。已知各杆件的长度均为l，刚度均为EI，受均布荷载作用，用位移法计算时的基本体系如图所示，求出位移法方程中的系数和自由项为（）<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202003/d7f9da9f3d7d4a1ca3aacc9d78b287bc.png" /> A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202003/4e6dd0d1ad09433f951a2ff19b298211.png"/>； B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202003/3b01d536637e445e841b61e5a9fa3506.png"/>。 C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202003/0969ea96f00849a09cccad36566fbf50.png"/>； D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202003/f03eca36624f4c51aff26a8015294edc.png"/>；

图示结构，汇交于结点A各杆端的力矩分配系数为：（）<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/d8fb108baf5043489469508c124eabc9.png"> A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/71af4aae8d3c4cc3a8236715c02d8dd0.png">,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/ccfc76583f3a4a17a1b8ae5d350c35c7.png">,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/0f214a006bf64228879035c5c64fba2a.png"> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/f6e2d4cb58c943b19e51aa37b929a34d.png">,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/7b66a4d0913142fabfdc2805b2971ecb.png">,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/54e6491e78754550be4f562e0849acd0.png"> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/115a0df0ea124266ae250912e8b572a1.png">,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/b686ba286d90499a9729e57a8fea8e32.png">,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/5c1a3965cc7245a0a9bca5f2eae645bf.png"> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/3b342699d2aa451d9a227dff4928c65f.png">,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202007/1d9ea5da536a4f18bd677cead25f28b2.png">

下列方程为伯努利方程的是（ ）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202108/0622f56257874ab19e680d587fd8a4fc.png"> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202108/5ce3fc785b724e3da7d07b8d6a0ecaf3.png"> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202108/ab3de1c35e9e419fa301a33bddd5ee0c.png">+<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202108/2c226f2daecf40448b08c3b26a4db60e.png"> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202108/88be95dd74814341a1894f32f073b9ec.png"><img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202108/00fbcbc7c3574f94934fa3adc8843ccf.png">

哪个标记用于表示 HTML 文档的结束？( ) A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202111/6c4425eb00dd44f2a456cd3fa4e18488.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202111/0db52a7ca0c0403d9f0e9f9784a1c655.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202111/0f4f1b4846f940448a74df9e286abc77.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202111/0dfd6a6c8d0f4ed2872185be16c2a849.png" />

变化的磁场激发的感应电场满足 ( ) A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202110/f636147417d144a4ba1c35b5c019b5bd.png" />,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202110/c85cf7ff1a2b4ac1a1690f3c06424b52.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202110/d249e3e9419547bb942b3e012cb266ac.png" />,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202110/a53d71dd9ba14f6889f4a46ecb00b923.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202110/466f114b82234936ab3612322e18ae5b.png" />,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202110/a5968023d69c492a9d3559f5a59d81ba.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202110/836158ae6c8944a780cf31e1deb309a0.png" />,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202110/9b1930e33b5e4af78f37e7d0ca350c2d.png" />