现给你如下器材：钢尺一把、木梳一把、音叉、乒乓球（系细线）、皮筋、鼓、纸张、小锤．请你任选器材，设计一个有关声现象的实验．提出问题：猜想或假设：器材：设计实验：探究结论：
提出问题：音调与什么有关？
猜想或假设：与振动的快慢有关；
器材及设计实验：钢尺一把，木梳．用钢尺拨动木梳齿，先慢后快，比较声音的高低；
探究结论：振动快音调高，振动慢音调低（答案不唯一）
Passage Three
| A chain of shops in East Yorkshire, England has been told that it would be a criminal offence to sell thousands of tubes of toothpaste made by a leading French manufacturer simply because the small print giving the firm importing it does not include the letters "UK". Under cosmetics regulations implementing 25 separate European Union instructions, unless the address is London, which is "a major city", the letters UK must be added. The suppliers response, when Gordon Rodgers’s A2Z chain asked them to take back the toothpaste, was that this would pose no problem, because trading standards officials elsewhere in Britain do not bother about such fault-finding to a very minute detail. A2Z, which sells a range of more than 10 000 household items from its 14 discount stores in Hull and East Yorkshire, first stumbled into these mysterious requirements of cosmetic labelling when summoned by East Yorkshire trading standards officials on a criminal charge of selling tubes of the same brand of toothpaste, Mentadent, designed for the South African market. These carried the name of a German distributor but no UK supplier. The council had no complaint about the toothpaste itself. It is common and legal practice for supermarkets and discount stores to buy up a wide range of branded products packaged by leading European and American manufacturers for non-EU markets. These can then be sold at prices lower than those recommended for identical products in Europe, which are only more expensive because EU consumers can supposedly afford to pay more. Council officials were quick to point out that they support the contribution this gray economy makes to "healthy competition". The only problem was that importers’ details must be given by the regulation formula. For a major city such as London only a postcode is necessary, but for other cities and towns the letters UK must be added. When A2Z asked how it was expected to examine the small print on the labelling of each of 10 000 products it carries, East Yorkshire replied that it was up to the firm to improve the quality of their inspection procedures. A2Z then supplied the council three weeks running with examples of similar products carrying "illegal labelling", bought from major supermarkets in the same area, asking why these large firms were not also prosecuted. The council said it "did not have the resources" to chase up every case of illegality, to which Mr. Rodgers responded that he "did not have the resources" to improve the quality of their inspection procedures, which the council was asking of him. Last week his firm’s case was adjourned. |
What can EU regulations cause
A．Additional costs.
B．Cheaper products.
C．Availability of a wider range of products.
D．Restrictions on supply.