如图所示圆球，判断其表面A点的三面投影作图是否正确。（ ）
举一反三
- 定积分<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/40a96e021d184b53859fdd4926e16b1b.png" />等于（ ） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/cde1094a25c3497f80373bc771f80513.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/54c773851e0348059f1ce37a91a948fc.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/e27823bdfcdc467faf41d0b330b00e15.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/6503ac83a84d4ae2ac241d6c3e33a59a.png" />
- 下列表达式正确的是（ ） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/75f7ea2db81e4968935ff7dbf6bcfe8d.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/be3e6f241e1d4dfbb709ad85ee2af5a7.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/4018abdbc95f48d090fe4a27c3f8f74b.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/9a49429b28964f2ca698879294f61c60.png" />
- 下列（ ）不属于中心支撑。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/b7b36299d8fb49c58fa83ef9ce64a739.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/73633e9d8616459490af2a472a7f9649.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/af19ae1f1e1f42ddbd45522c9ddbbea7.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/11cef2be0b5b46f6a30e71db95fd8476.png" />
- 用OLS估计经典线性模型<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/eb8ed6ad126745fa8aa3e6527980a6fa.png" />，则样本回归直线通过的点是（ ）。 A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/64ecbf5286eb4fa083d00e749d64f6f2.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/21b327b2cfb4461aae281b0359e80994.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/fad234b8a5eb41f9bb6ebf585aa414c4.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/9355d5aaf7ad484e8231e959141f5d68.png" />
- 下列定积分大小关系正确的是（ ） A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/6425a5641347401c96cfe410e9a49a6a.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/1a745dfce5354003a4b0b26edd8e2059.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/a953f9a57c264d6cb7b1e025a189af23.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202103/34dcf8af5beb4e5685097ef3fd73ae3d.png" />