一期梅毒平均潜伏期为（）A.1周 B.2～3周 C.4周 D.2个月 E.3 发布时间：2017-07-26 16:16 │ 来源：www.tikuol.com 题型：单项选择题 问题： 一期梅毒平均潜伏期为（）A.1周 B.2～3周 C.4周 D.2个月 E.3个月
题型：单项选择题 阅读短文，从方框中选择适当的单词填空。 next, many, look, turn, tired Welcome to London! Would you please have a 1______ at your map? We are standing in this square, which is in the middle of London. You'll see 2______ places of great interest. First you can go along the Red Street to Buckingham Palace. Then, 3______ left and to go Big Ben, the famous big clock in the world. When you are 4______, the best way to see London is by boat. You can get the boat near Big Ben. The beautiful sceneries along the river will make you relaxed. Get off the boat at Tower Bridge. There you can see the Tower of London 5______ to the bridge. The Tower of London is the city's oldest palace. It is 900 years old. 查看答案
题型：单项选择题 下列实验操作及现象与结论对应关系正确的一组是 实验操作实验现象实验结论A适量二氧化碳通入氯化钡溶液中产生沉淀碳酸的酸性比盐酸弱B二氧化硫通入溴水中溶液褪色二氧化硫有漂白性C取少量某无色溶液，先滴加氯水，再加入少量四氯化碳，振荡、静置溶液分层，下层呈橙红色原无色溶液中一定有溴离子D将铜片放入浓硝酸中产生大量无色气体，溶液呈蓝绿色只体现浓硝酸的强氧化性 查看答案
题型：单项选择题 “直到1500年以前，大西洋一直是一道栅栏，一个终点。但在1500年左右，它一变而成为一座桥梁，一个启程之地。”关于这一变化理解不正确的是：（）A.源于新航路的开辟B.推动世界市场雏形的形成C.以汽船的发明为前提D.对于美洲和非洲原住民意味着灾难 查看答案