氯丁橡胶的牌号代号是()
A.CR
B.LD
C.CH
D.AD
参考答案:A
What's her name? _____. [ ]
A. His name is Kate
B. Her name is Kate
C. She's name is Ann
D. Its Kate
当烟草叶片受到甲种蛾幼虫的采食刺激后,会释放出挥发性的化学物质。这种化学物质白天会吸引甲种蛾幼虫的天敌,夜间会驱赶乙种蛾,使其不能在烟草叶片上产卵(乙种蛾幼虫也采食烟草叶片)。试回答:
甲种蛾幼虫与乙种蛾幼虫的种间关系是:()。