由曲线[imgwidth="156"height="53"src="https://p.ananas.chaoxing.com/star3/origin/00e346dd386ef544f5052fb5c90e1372.png"]、[imgwidth="37"height="19"src="https://p.ananas.chaoxing.com/star3/origin/8fad2786802119320b27fc6647707e0d.png"]和[imgwidth="35"height="21"src="https://p.ananas.chaoxing.com/star3/origin/27d8820aa177e50656e6ffa3c6225a67.png"]围成的平面图形绕[imgwidth="15"height="17"src="https://p.ananas.chaoxing.com/star3/origin/b3048d8c2bbe74ff01f7d3c8915bfdef.png"]轴旋转一周所得旋转体的体积[imgwidth="28"height="19"src="https://p.ananas.chaoxing.com/star3/origin/c9d9123939953c49b1e9b6492e79f835.png"](). A: imgwidth="55"height="21"src="https://p.ananas.chaoxing.com/star3/origin/3bcbb56de7b78a2ff7eff984ee56642e.png">; B: ; C: ; D: .

设[imgwidth="71"height="25"src="https://p.ananas.chaoxing.com/star3/origin/75ffa9533e6ab79bc0cfb8fd5a03fb9e.png"],则[imgwidth="39"height="23"src="https://p.ananas.chaoxing.com/star3/origin/424d5c9d46833a5ab8942dcd75ce5a8c.png"]在[imgwidth="37"height="21"src="https://p.ananas.chaoxing.com/star3/origin/9ee84cb4b1771fa6c046eaa6c45bb946.png"]上的平均值为(). A: imgwidth="16"height="45"src="https://p.ananas.chaoxing.com/star3/origin/f163ea87a82b79497196f437c30b8320.png">; B: ; C: ; D: .

,当在连续时,___https://p.ananas.chaoxing.com/star3/origin/2d7d11725699807cb0b07057a0e6aa1b.pnghttps://p.ananas.chaoxing.com/star3/origin/8afd799308433cf0c1bf99426a50b068.pnghttps://p.ananas.chaoxing.com/star3/origin/6fc93eeaca0b4e2eeb3232571be04039.pnghttps://p.ananas.chaoxing.com/star3/origin/9ac20ba1a54c062278a4c0602f36ab4c.png

识图题3：这是什么结构https://p.ananas.chaoxing.com/star3/origin/c6be927f491ee20405c44f4e658f08c3

设是圆,则https://p.ananas.chaoxing.com/star3/origin/d8b5edc9a2457c461a3685877f8606ab.pnghttps://p.ananas.chaoxing.com/star3/origin/5f3c1256fa1597901980dc868dfb57f7.pnghttps://p.ananas.chaoxing.com/star3/origin/1932e2a8e9452d4d6f94177a0ca40384.pnghttps://p.ananas.chaoxing.com/star3/origin/5785decddcc5b175015fc7c46d4d8405.png