家鹅、家鸭是人类驯化较早的鸟类．图1显示了家鸭、家鹅是由绿头鸭、鸿雁、灰雁等物种进化而来．中国是世界上拥有鹅品种最多的国家，资源丰富，同时也是生物多样性受到严重威胁的国家之一．

（1）ST、XP、WX、HY、LD5个鹅品种中，与ST亲缘关系最近的是____ ．

ST与LD之间形态和大小方面的差异较大（图2），它们体现的是____ 多样性．

A、遗传多样性    B、物种多样性      C、群落多样性     D、生态系统多样性

（2）若图1中的①表示的是人工选择，以下说法正确的是____ （多选）

A．图中②可以表示自然选择，自然选择的因素是自然界的各种环境条件

B．人工选择使得鸿雁根据人类的各种需求定向变异，由此形成不同的家鹅品种

C．人工选择的过程中由于没有形成新物种，因此不出现种群基因频率的改变

D．人工选择的速度较快，自然选择需要漫长的岁月．自然选择的结果是保存对生物自身有利的各种性状．

（3）由原始物种X进化形成绿头鸭、鸿雁、灰雁的标志是____．关于这一进化历程的内因以及外因的分析可描述为____ ．

（4）若在某地养殖场中，鹅的白羽（W）对灰羽（w）为显性．在一个由600只白羽鹅和400只灰羽鹅组成的种群中，若杂合子占所有个体的40%，那么隐性基因w在该种群内的基因频率为____ ．

A．20%          B．40%           C．60%          D．80%

已知抛物线y=a（x﹣m）²+n与y轴交于点A，它的顶点为点B．点A、B关于原点O的对称点分别是点C，D．若点A，B，C，D中任何三点都不在一直线上，则称四边形ABCD为抛物线的伴随四边形，直线AB为抛物线的伴随直线．

阅读下面材料，在空白处填入适当的内容(1个单词)或括号内单词的正确形式。

Lori：Good morning, Chuck. Are you here____(wait) for Professor Johnson?

Chuck：Oh, yes. Good morning, Lori. The professor asked me to come here ____(have) an interview. Do you know something about the job as ____ teacher's assistant?

Lori：Oh, yes. I know all about it ____ Ihave work experience in this field. Last year, I did it for a long time.

Chuck：Really? How did you like ____？

Lori：Well, actually I think it was____(good) I had ever had at school. I was paid nine dollars an hour, which____(be) three dollars more than the school post office paid us.

Chuck：Yeah, I bet this is a good salary. But what did you do?

Lori：My responsibility was to help Professor Johnson grade the students' homework. It wasn't hard and the professor was always available ____ there were any questions. I ____ improve myself through doing this job.

Chuck：I think I would enjoy this kind of work. But I'm a little worried about how much ____ it might take.

Lori：Only about five or six hours a weekand you can do that in your room.

Chuck：It sounds good.