3.如图为理想状态下自然环境中某生物的种群数量变化曲线,下列说法正确的是( ) ①阴影部分表示环境中影响种群增长的阻力 ②a为“J”型曲线,b为
Dear Victor,I am a college student. Nowadays games on the net are very popular with college students. Some of my roommates are very interested in them. They not only play games in their free time, but
第三部分 任务型阅读(共两节,满分35分) When Carla Fisher and her husband announced plans to travel the globe with their young daughters for a year, some friends called them crazy.
已知:如图,四边形ABCD中,AC平分∠BAD,∠B和∠D都是直角.⑴ 求证:BC=CD.⑵ 若将原题中的已知条件“∠B和∠D都是直角”放宽为“∠B和∠D互为补角”,
在一个密闭容器中放入X、Y、Z、W四种物质,在一定条件下发生化学反应,一段时间后,测得有关数据如下表。则关于此反应的认识不正确的是物 质X
.(2010·浙江温州中学高三9月月考)3. The actress looked so charming in her beautiful dress that we took ______ pictures with her. A. a great many of B. masses o
26.1842年的《南京条约》第十条规定:“前第二条内言明开关俾英国商民居住通商之广州等五处,应纳进口、出口货税、饷费,均宜秉公议定则例,由部
某植物种群中,AA个体点16%,aa个体占36%,该种群随机交配产生的后代中AA个体百分比、A基因频率和自交产生的后代中AA个体百分比、A基因频率的变化