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[{"id":2763,"subject":"历史","grade":"七年级","stage":"初中","type":"选择题","content":"唐朝时期,长安城是当时世界上最大的城市之一,也是中外文化交流的重要中心。许多外国使节、商人和留学生来到长安,带来了异域的文化和商品。以下哪一项最能体现唐朝长安城作为中外文化交流中心的特点?","answer":"B","explanation":"本题考查唐朝中外交流的特点,重点在于理解长安城作为国际大都市的文化包容性。选项B正确,因为史料记载,唐朝长安城内有大量来自波斯(今伊朗)、大食(阿拉伯帝国)等地的商人,同时存在景教(基督教聂斯脱利派)、祆教(拜火教)等外来宗教的寺庙,这直接体现了中外文化在长安的交融。选项A错误,因为市舶司是宋朝设立的机构,唐朝并未设置;选项C描述的是城市管理制度,虽符合史实,但不直接体现‘中外交流’;选项D强调的是政治功能,与文化交流无关。因此,B项最能体现长安作为中外文化交流中心的特点。","solution_steps":"","common_mistakes":"","learning_suggestions":"","difficulty":"中等","points":1,"is_active":1,"created_at":"2026-01-12 10:40:03","updated_at":"2026-01-12 10:40:03","sort_order":0,"source":null,"tags":null,"analysis":null,"knowledge_point":null,"difficulty_coefficient":null,"suggested_time":null,"accuracy_rate":null,"usage_count":0,"last_used":null,"view_count":0,"favorite_count":0,"options":[{"id":"A","content":"选项A","is_correct":0},{"id":"B","content":"选项B","is_correct":1},{"id":"C","content":"选项C","is_correct":0},{"id":"D","content":"选项D","is_correct":0}]},{"id":1964,"subject":"数学","grade":"七年级","stage":"初中","type":"选择题","content":"某学生在研究某河流一周内每日水位变化时,记录了连续7天的水位数据(单位:米):3.2, 4.1, 3.8, 4.5, 3.9, 4.3, 3.6。为了分析这组数据的集中趋势,该学生决定计算这组数据的中位数和平均数。已知中位数是将数据按大小顺序排列后位于中间的值,平均数是所有数据之和除以数据个数。请问这组数据的中位数与平均数之差最接近以下哪个数值?","answer":"A","explanation":"本题考查数据的收集、整理与描述中中位数和平均数的计算及其比较。首先将7天水位数据从小到大排序:3.2, 3.6, 3.8, 3.9, 4.1, 4.3, 4.5。由于数据个数为7(奇数),中位数是第4个数,即3.9。接着计算平均数:(3.2 + 4.1 + 3.8 + 4.5 + 3.9 + 4.3 + 3.6) ÷ 7 = 27.4 ÷ 7 ≈ 3.914。然后计算中位数与平均数之差:|3.9 - 3.914| ≈ 0.014,最接近选项A(0.05)。虽然0.014略小于0.05,但在给定选项中最接近,因此选A。","solution_steps":"","common_mistakes":"","learning_suggestions":"","difficulty":"中等","points":1,"is_active":1,"created_at":"2026-01-07 14:47:49","updated_at":"2026-01-07 14:47:49","sort_order":0,"source":null,"tags":null,"analysis":null,"knowledge_point":null,"difficulty_coefficient":null,"suggested_time":null,"accuracy_rate":null,"usage_count":0,"last_used":null,"view_count":0,"favorite_count":0,"options":[{"id":"A","content":"0.05","is_correct":1},{"id":"B","content":"0.10","is_correct":0},{"id":"C","content":"0.15","is_correct":0},{"id":"D","content":"0.20","is_correct":0}]},{"id":566,"subject":"数学","grade":"初一","stage":"初中","type":"选择题","content":"在一次环保知识竞赛中,某班级共收集了120份有效问卷。统计结果显示,有45份问卷支持‘垃圾分类’,有38份支持‘节约用水’,其余支持‘绿色出行’。请问支持‘绿色出行’的问卷数量是多少?","answer":"A","explanation":"题目考查的是数据的收集、整理与描述中的基本运算能力。已知总问卷数为120份,其中支持‘垃圾分类’的有45份,支持‘节约用水’的有38份,其余为支持‘绿色出行’的问卷。因此,支持‘绿色出行’的问卷数量为:120 - 45 - 38 = 37(份)。计算过程为:120 - 45 = 75,75 - 38 = 37。故正确答案为A。","solution_steps":null,"common_mistakes":null,"learning_suggestions":null,"difficulty":"简单","points":1,"is_active":1,"created_at":"2025-12-29 19:33:53","updated_at":"2025-12-30 11:11:27","sort_order":0,"source":null,"tags":null,"analysis":null,"knowledge_point":null,"difficulty_coefficient":null,"suggested_time":null,"accuracy_rate":null,"usage_count":0,"last_used":null,"view_count":0,"favorite_count":0,"options":[{"id":"A","content":"37","is_correct":1},{"id":"B","content":"42","is_correct":0},{"id":"C","content":"47","is_correct":0},{"id":"D","content":"53","is_correct":0}]},{"id":1786,"subject":"数学","grade":"七年级","stage":"初中","type":"选择题","content":"某学生在平面直角坐标系中绘制了一个四边形ABCD,已知点A的坐标为(0, 0),点B的坐标为(4, 0),点C的坐标为(5, 3),点D的坐标为(1, 3)。该学生想判断这个四边形是否为平行四边形,并计算其面积。以下说法正确的是:","answer":"A","explanation":"首先判断四边形是否为平行四边形。根据坐标,可计算各边向量:向量AB = (4, 0),向量DC = (5-1, 3-3) = (4, 0),故AB与DC平行且相等;向量AD = (1, 3),向量BC = (5-4, 3-0) = (1, 3),故AD与BC也平行且相等。因此两组对边分别平行且相等,四边形ABCD是平行四边形。接着计算面积:可利用底乘高。以AB为底,长度为4,点D到AB(x轴)的垂直距离为3,故面积为4 × 3 = 12。或者用向量叉积法:|AB × AD| = |4×3 - 0×1| = 12。因此正确答案为A。","solution_steps":null,"common_mistakes":null,"learning_suggestions":null,"difficulty":"困难","points":1,"is_active":1,"created_at":"2026-01-06 15:56:29","updated_at":"2026-01-06 15:56:29","sort_order":0,"source":null,"tags":null,"analysis":null,"knowledge_point":null,"difficulty_coefficient":null,"suggested_time":null,"accuracy_rate":null,"usage_count":0,"last_used":null,"view_count":0,"favorite_count":0,"options":[{"id":"A","content":"四边形ABCD是平行四边形,面积为12平方单位","is_correct":1},{"id":"B","content":"四边形ABCD是平行四边形,面积为10平方单位","is_correct":0},{"id":"C","content":"四边形ABCD不是平行四边形,但面积为12平方单位","is_correct":0},{"id":"D","content":"四边形ABCD不是平行四边形,面积为10平方单位","is_correct":0}]},{"id":2315,"subject":"数学","grade":"八年级","stage":"初中","type":"选择题","content":"某学生在整理班级同学身高数据时,记录了5名同学的身高(单位:cm)分别为:158, 162, 160, 165, 155。若再加入一名同学的身高后,这组数据的平均数恰好为160 cm,则这名同学的身高是多少?","answer":"A","explanation":"首先计算原有5名同学身高的总和:158 + 162 + 160 + 165 + 155 = 800(cm)。设新加入同学的身高为x cm,则6名同学的总身高为(800 + x) cm。根据题意,平均数为160 cm,因此有方程:(800 + x) ÷ 6 = 160。解这个方程:800 + x = 960,得x = 160。所以这名同学的身高是160 cm,正确答案为A。","solution_steps":"","common_mistakes":"","learning_suggestions":"","difficulty":"简单","points":1,"is_active":1,"created_at":"2026-01-10 10:47:15","updated_at":"2026-01-10 10:47:15","sort_order":0,"source":null,"tags":null,"analysis":null,"knowledge_point":null,"difficulty_coefficient":null,"suggested_time":null,"accuracy_rate":null,"usage_count":0,"last_used":null,"view_count":0,"favorite_count":0,"options":[{"id":"A","content":"160 cm","is_correct":1},{"id":"B","content":"158 cm","is_correct":0},{"id":"C","content":"162 cm","is_correct":0},{"id":"D","content":"164 cm","is_correct":0}]},{"id":796,"subject":"数学","grade":"初一","stage":"小学","type":"填空题","content":"在一次班级图书角整理活动中,某学生统计了上周同学们借阅的图书数量,发现科技类图书比文学类图书多借出8本,两类图书共借出46本。设文学类图书借出x本,则科技类图书借出___本,根据题意可列方程为___。","answer":"x + 8;x + (x + 8) = 46","explanation":"题目中明确指出科技类图书比文学类多8本,若文学类借出x本,则科技类为x + 8本。两类图书共借出46本,因此可列出方程:x + (x + 8) = 46。本题考查用字母表示数量关系及建立一元一次方程的能力,属于‘一元一次方程’知识点,符合七年级教学要求。","solution_steps":null,"common_mistakes":null,"learning_suggestions":null,"difficulty":"简单","points":1,"is_active":1,"created_at":"2025-12-30 00:14:51","updated_at":"2025-12-30 11:11:27","sort_order":0,"source":null,"tags":null,"analysis":null,"knowledge_point":null,"difficulty_coefficient":null,"suggested_time":null,"accuracy_rate":null,"usage_count":0,"last_used":null,"view_count":0,"favorite_count":0,"options":[]},{"id":918,"subject":"数学","grade":"初一","stage":"初中","type":"填空题","content":"在一次班级大扫除中,某学生负责统计各小组打扫的区域面积。已知第一组打扫了 (2x + 3) 平方米,第二组打扫了 (x - 1) 平方米,第三组打扫了 (4x + 2) 平方米。如果三个小组总共打扫了 35 平方米,那么 x 的值是 ___。","answer":"5","explanation":"根据题意,将三个小组打扫的面积相加等于总面积:(2x + 3) + (x - 1) + (4x + 2) = 35。先合并同类项:2x + x + 4x = 7x,3 - 1 + 2 = 4,所以得到方程 7x + 4 = 35。两边同时减去 4 得 7x = 31,再两边同时除以 7 得 x = 5。因此,x 的值是 5。","solution_steps":null,"common_mistakes":null,"learning_suggestions":null,"difficulty":"简单","points":1,"is_active":1,"created_at":"2025-12-30 02:40:59","updated_at":"2025-12-30 11:11:27","sort_order":0,"source":null,"tags":null,"analysis":null,"knowledge_point":null,"difficulty_coefficient":null,"suggested_time":null,"accuracy_rate":null,"usage_count":0,"last_used":null,"view_count":0,"favorite_count":0,"options":[]},{"id":653,"subject":"数学","grade":"初一","stage":"初中","type":"填空题","content":"在一次班级环保活动中,某学生收集了若干个塑料瓶和玻璃瓶,其中塑料瓶的数量比玻璃瓶多8个。若两种瓶子一共有36个,那么玻璃瓶有___个。","answer":"14","explanation":"设玻璃瓶的数量为x个,则塑料瓶的数量为x + 8个。根据题意,两种瓶子总数为36个,可列方程:x + (x + 8) = 36。化简得2x + 8 = 36,解得2x = 28,x = 14。因此,玻璃瓶有14个。本题考查一元一次方程的实际应用,属于七年级数学课程内容。","solution_steps":null,"common_mistakes":null,"learning_suggestions":null,"difficulty":"简单","points":1,"is_active":1,"created_at":"2025-12-29 22:11:43","updated_at":"2025-12-30 11:11:27","sort_order":0,"source":null,"tags":null,"analysis":null,"knowledge_point":null,"difficulty_coefficient":null,"suggested_time":null,"accuracy_rate":null,"usage_count":0,"last_used":null,"view_count":0,"favorite_count":0,"options":[]},{"id":374,"subject":"数学","grade":"初一","stage":"小学","type":"选择题","content":"在一次班级数学测验中,某学生记录了5名同学的分数分别为:78,85,92,88,82。如果老师要求计算这5名同学的平均分,那么正确的计算结果是多少?","answer":"B","explanation":"要计算5名同学的平均分,需要先将所有分数相加,再除以人数。计算过程如下:78 + 85 + 92 + 88 + 82 = 425。然后将总分425除以人数5,得到425 ÷ 5 = 85。因此,这5名同学的平均分是85分,正确答案是B。本题考查的是数据的收集、整理与描述中的平均数计算,属于七年级数学课程内容,难度为简单。","solution_steps":null,"common_mistakes":null,"learning_suggestions":null,"difficulty":"简单","points":1,"is_active":1,"created_at":"2025-12-29 15:49:54","updated_at":"2025-12-30 11:11:27","sort_order":0,"source":null,"tags":null,"analysis":null,"knowledge_point":null,"difficulty_coefficient":null,"suggested_time":null,"accuracy_rate":null,"usage_count":0,"last_used":null,"view_count":0,"favorite_count":0,"options":[{"id":"A","content":"83","is_correct":0},{"id":"B","content":"85","is_correct":1},{"id":"C","content":"87","is_correct":0},{"id":"D","content":"89","is_correct":0}]},{"id":3,"subject":"数学","grade":"初二","stage":"初中","type":"选择题","content":"二元一次方程组{x + y = 5, 2x - y = 1}的解是?","answer":"C","explanation":"使用加减消元法,将两个方程相加消去y:(x + y) + (2x - y) = 5 + 1,得到3x = 6,解得x = 2。将x = 2代入第一个方程:2 + y = 5,解得y = 3。","solution_steps":null,"common_mistakes":null,"learning_suggestions":null,"difficulty":"中等","points":1,"is_active":1,"created_at":"2025-08-29 16:33:04","updated_at":"2025-08-29 16:33:04","sort_order":0,"source":null,"tags":null,"analysis":null,"knowledge_point":null,"difficulty_coefficient":null,"suggested_time":null,"accuracy_rate":null,"usage_count":0,"last_used":null,"view_count":0,"favorite_count":0,"options":[{"id":"A","content":"x = 1, y = 4","is_correct":0},{"id":"B","content":"x = 3, y = 2","is_correct":0},{"id":"C","content":"x = 2, y = 3","is_correct":1},{"id":"D","content":"x = 4, y = 1","is_correct":0}]}]