已知:AB⊥BC,AD⊥DC,∠1=∠2,问:△ABC≌△ADC吗?说明理由.
如图是a、b、c三种物质的溶解度曲线,a与c的溶解度曲线相交于P点.据图回答:
(1)t1℃时,a物质的溶解度____b物质的溶解度.(填“>“、“<“或“=“)
(2)t2℃时a、b、c三种物质的溶解度按由小到大的顺序排列是____ (填写物质序号).
(3)t2℃时,将50克a物质溶于150克水中得到的溶液是____ (填“饱和“或“不饱和“)溶液.
(4)将t2℃时等质量的a、b、c物质的饱和溶液降温到t1℃时,析出晶体最多的是 ____ .
根据对话内容,从方框中选择适当的选项补全对话, 选项中有两项是多余的。
Jim: It’s Sunday today. I’m not going to school. ____ Dad?Father: Let’s look at the map.Mother: Shall we watch TV at home?Jim: No.____ Father: Let me see. We shall go to that park. It’s near the sea.Jim: ____ Father: We shall have a swim in the sea. Then we shall have a meal at the seaside.Jim: Great!Father: Come on! Let’s all get into the car.Jim: ____ Dad?Father: There’s something wrong with the car.Mother: ____
∵∠1=∠2(已知),
∠AEF =∠1 ____,
∴ ∠AEF =∠2 (等量代换),
∴ AB∥CD ____,
∴ ∠BEF = ∠CFE ____,
∵∠3=∠4(已知)
∴ ∠BEF -∠4= ∠CFE -∠3 (等式的基本性质),
即∠____= ∠HFE
∴ EG∥FH ____.