填入一个适当的词补全对话，每空一词。

A: Hello, is that Tom speaking?

 B: Hello, this is Tom.

 A: Have you made a plan for this weekend?

 B: Not yet. I'm____ busy to think about it. What is your idea?

 A: What about playing basketball at the City Gym this Saturday?

 B: Good idea. When shall we meet?

 A: Let's ____it 8: 00 a.m.

 B:All right. ____  are we going to meet?

 A: At the bus stop near our school.

 B: How  ____ does it take to go to the gym by bus?

 A: About half an hour.

 B: Why not go there by subway? The traffic may be very awful on Saturday morning.

 A: I can't agree with you any____   Then we can meet at the subway station.

 B: Do you know what the____ will be like that day?

 A: The radio says it will be rainy.

 B: ____  better take umbrellas with us.

 A: OK. I think we'll have fun together. I'm looking forward to that. See you.

 B: See you.

下图“桑基鱼塘”模式，是现代农业的典型，获得了鱼、蚕、桑、气的全面丰收。

已知圆心（a，b）（a＜0，b＜0）在直线y=2x+1上的圆，若其圆心到x轴的距离恰好等于圆的半径，在y轴上截得的弦长为 $2\sqrt{5}$ ，则圆的方程为（  ）

以秦岭—淮河为界，以南的地区冬季一月平均气温在____以上，以北地区年降水量在____以下。

初速为零的正离子经过电势差为U的电场加速后，从离子枪T中水平射出后进入无限大的磁感应强度B的匀强磁场中，距离离子枪右侧d处有一长为d的正对平行金属板，金属板间距也为d，且两金属板中线恰好与离子从离子枪出射的初速度方向共线，如图所示．不计重力，离子荷质比在什么范围内离子才能打在金属板上．