管道外径≤14"时，标识的大小为（） A.3～5mm B.4～6mm C.7～10m
题型：单项选择题
问题：
管道外径≤14"时，标识的大小为（）
A.3～5mm
B.4～6mm
C.7～10mm
D.8～12mm
题型：单项选择题
完形填空（二）（本题共15小题，满分30分）
阅读下面短文，根据文意，将方框内所给的词或短语的适当形式填入相应的空白处，使短文的意思完整。（每个词只能使用一次）（本题共十小题，每小题2分，满分20分）
We all need a healthy environment, but we produce waste every day and it__小题1:__ our environment. Though we are young, we can still do something to help. In fact, even the simplest _小题2:__activities can make a real difference to the environment. Here are some ideas for you.
Reduce means “use less”. Don’t waste things. This __小题3:__money and reduces pollution and waste going into the environment. Before we buy something new, think ___小题4:____it is really necessary—or maybe the old one will be just as good! When we do buy things, choose local products if __小题5:_____ and try not to buy too many things from abroad.
Reuse means “use again”. Use things for as long as possible. When we buy things, make sure that they __小题6:__ a long time. We should look after them__小题7:_ they will last and we should repair them if we can instead of throwing them away and buying new ones. Don’t use a paper cup or a paper bag. It’s better to use a china cup and a lunch box because you can use them __小题8:__.
Recycle means “change things into something else”. Although it takes ___小题9:_ to change something into something else, it’s better than throwing things away or burning them. Find out what can be recycled in your_小题10:__ and take part in recycling programmes. We should also buy products made from recycled materials, such as recycled paper, to help save trees.