题目

（8分）某同学要测量一均匀新材料制成的圆柱体的电阻率ρ。步骤如下： （1）用游标为20分度的卡尺测量其长度如图，由图可知其长度为              mm； （2）用螺旋测微器测量其直径如右上图，由图可知其直径为         mm； （3）用多用电表的电阻“×10”挡，按正确的操作步骤测此圆柱体的电阻，表盘的示数如图，则该电阻的阻值约为               Ω。 （4）该同学想用伏安法更精确地测量其电阻R，现有的器材及其代号和规格阅读理解。     Su Hua is studying at Cambridge, UK. She has bought a bicycle and is worried about security. Her friend, Kate, found this article and sent it to her.     Introduction      A lot of crime is against bicycles. About 150,000 bicycles are stolen every year and most are never found. You can prevent this happening by following a few careful steps.     Basic Security     Do not leave your bicycle in out-of-the-way places. Always lock your bicycle when you leave. Secure it to lampposts or trees. Take off smaller parts and take them with you, for example lights and saddles(车座).     Locks      Get a good lock. There are many different types in the shop. Buy one that has been tested against attack. Ask for a recommendation from a bike shop.      Marking      Security marking your bike can act as a deterrent to a thief. It can also help the police find your bicycle. It should be clearly written and include your postcode and your house or flat number. This will provide a simple way to identify your bicycle.     Registration     There are a number of companies who will security mark your bicycle for you. They will then put your registration number and personal details on their computer database. Then if your bicycle is found it will be easy to contact you.     Finally       Keep a record of the bicycle yourself: its make, model and registration number. You can even take a photograph of it, this will prove the bicycle belongs to you.1. Which part of the article gives you information on how to lock up your bicycle when you leave it?A. Locks      B. Marking       C. Registration       D. Basic Security2. The underlined phrase "act as a deterrent to a thief" means__________ .A. help you recognize your bike           B. help the police find your bicycleC. stop someone stealing your bicycle       D. stop you worrying about your bike3. The article advises you to keep a record of your bicycle ____________. A. in the bike shop and your computerB. in a police station and security companyC. in a security company and your universityD. by yourself and in a security company4. The main purpose of this article is _____________. A. to tell you what to do if your bicycle is stolenB. to suggest ways of keeping your bicycle safeC. to give you advice on where to buy a good lockD. to say why you shouldn't keep your bicycle in a quiet place