读图回答下列问题

（1）写出A、B山脉的名称：A是____ ，B是____ 成为我国重要地理分界线的是____ （填字母），这条线和____ 毫米等降水量线基本一致；这座山以北冬季河流____ ，以南冬季河流____ （填“结冰”或“不结冰”）。
（2）属于我国最东端的点是____ （填序号），属于我国最西端的点是____ (填序号)，① 地比② 地降水多的原因是____ 。
（3）⑤⑥ 两地所在的温度带：⑤ 是____ ⑥是____ ，产生这种差异的原因是____ 。
（4）③ 和④ 的连线是我国最重要的____ ，这是我国著名的人口地理学家____ 先生1935年提出的。

图为阿尔卑斯山的垂直地带分布示意图，读图，该山地（   ）

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。

    The truth ____ trees are vital to our life is not a secret. They provide us withfood, wood and most ____(important), oxygen. Now there is one more thing we canadd to this list—blocking out harmful bacteria from water.

    The discovery ____(make) by a team____(consist) of scientists from the Massachusetts Institute of Technology(MIT) and high school students ____ were seeking a natural water filter—onethat would help communities in developing countries that do not have ____(accessible)to modern water filter systems.

    The ____(research), led by Professor RohitKarnik, decided to turn to trees for help because they could allow liquid toflow through, while blocking out air bubbles.

    They began by cutting 1.5­inch­wide sectionsof tree bark from the branches of a white pine tree. The people related thentested the wood's filtering ability by pouring water containing red dyeparticles of different sizes through. ____ their amazement, they found that itwas effective in trapping all the particles. ____(encourage), the teamconducted ____ experiment, this time with water that contained bacteria. Sureenough, the sapwood held back 99% of the bacteria, allowing only 1% to flowthrough.