第一次世界大战前形成的帝国主义两大军事侵略集团的核心是（    ）

某地建设了以沼气池为核心的生产自净农业生态系统，图1是该生态系统的结构模式图，图2是沼气池的结构模式图．请回答下列问题：

（1）该自净农业生态系统的设计主要根据生态工程的____ 原理．与传统农业生态系统相比，该生态系统能减轻环境污染的主要原因一是减少了秸秆的焚烧；二是____ ．

（2）图1中的“基石”是____ ．沼气池中有产甲烷菌等微生物，其生态学作用主要是____．

（3）图2中进料口下端开口位于沼液层的目的是____ ．独立的沼气池不能看作一个生态系统，其理由是____ ．

It is August 2050. Mrs Peng and Mr Yu are writing about hotels and houses on their posts.

The Hotel Whale

  The Hotel Whale is built (A) 在水下. It is in the shape of a whale. This hotel has 50 bedrooms, a cafe and a shopping centre.

Mrs Peng: “When we were staying at the hotel recently, my children watched the fish outside their bedroom window. (B) They were never bored.”

Forever Green Houses

  These houses are both “green” and “smart”. There is glass outside the houses. Heat is held under the glass and is then used as energy for (C) each house. In the bathroom, your medicine cupboard is connected to your doctor’s computer. In the kitchen, your smart fridge tells the supermarket’s computer when you (D) need more food.

Mr Yu: “When we were living in our old house, we were using more energy. I would certainly recommend Forever Green Houses to my friends. (E) They will satisfy everyone.”

发热对人体有害方面是（　　）