最低共熔点
参考答案：
物料在加热过程中，由两种或两种以上组分开始出现液相的温度的点。
阅读理解，根据上下文意思选择正确的答案。
It is a nice day. John and Jim go to a nature park. There is a big forest in the park. There is a beautiful lake
near the forest and they can see some fishes in the lake. There is a bridge over the river in front of the lake. They
take some pictures on the bridge. They want to climb the mountains, but they have no time.
1. Are there any trees in the park?
A. Yes, there are.
B. No, there aren't.
2. What do they do on the bridge?
A. They go fishing.
B. They take some pictures.
3. Is there a lake near the forest?
A. Yes, there is.
B. No, there isn't.
4. Are there any fish in the lake?
5. Do John and Jim climb the mountains?
A. Yes, they do.
B. No, they don't.
中央谷地是纵贯美国太平洋沿岸加利福尼亚州中部的平原，南北长约720km，东西宽约60～100km，是加州重要的农业区。下图为部分谷地水系分布图，中央谷地最可能的地质成因是（）
A.板块张裂地壳水平错断
B.板块挤压地壳断裂陷落
C.板块张裂地壳褶皱凹陷
D.板块俯冲地壳水平张裂
