以下是一些系统函数的收敛域，则其中稳定的是()。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/c05f69717a214356a5f18a4b6899ca6a.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/fc079e2aad0a4f6285b861d7ed3b5cee.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/4144dae3ee5e497bbe5567f664e1045a.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/ac101952a39c456da9f0443233498d24.png" >

总蒽醌的乙醚溶液中，采用5%NaHCO3溶液萃取，碱水层的成分是：（） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/e780e08ee0d5455e8886c395f89f45da.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/49b958abd18b4dbcbcbe8f03ec657948.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/5737c8a8d44b49bcb90bfe2c4407caeb.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/a55c5696f23c45e68067ddf9e9506ec1.png" >

插销穿过水平放置的平板上的圆孔，在其下端受一拉力F作用。该插销的剪切面面积和挤压面面积分别等于（）。<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/5d23680126824bfab3f4f4993ca84f92.png"> A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/0fb38a6e2ec5434f85408b2720422fc1.png"> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/f4d0398cfbe84d15bb6369dc4c837211.png"> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/5075a462f16045358ac45a636012cc27.png"> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/6754d0277d3f4f07aee0ce613bfca1d4.png">

在一绝热箱内，一电阻丝浸入水中，通以电流。若以水和电阻丝为系统，其余为环境，则（）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/a9f04b31565743a8b96f21c4ad1d5486.png" > B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/8897c7e012d44584b8ed795db89f0c8f.png" > C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/cad4626c78cd47d781566e33198e1c5a.png" > D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202005/44811b349b8f47b8a330c85bb73d83a2.png" >

通过点<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/a13927df1bf542dfa036a32b10364f69.png" />的拉格朗日插值基函数<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/65695a42c7a14b649b6aa4fb68f7e499.png" />满足( ) A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/99af333f3e934ef6a75022ee1e728b53.png" />＝1，<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/7769611ac5cd4c93975be7c41a49ae71.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/99af333f3e934ef6a75022ee1e728b53.png" />＝1，<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/7769611ac5cd4c93975be7c41a49ae71.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/99af333f3e934ef6a75022ee1e728b53.png" />＝0，<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/7769611ac5cd4c93975be7c41a49ae71.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/99af333f3e934ef6a75022ee1e728b53.png" />=0，<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/f80e8e400f3f4916bcaf6b5fde757f16.png" />