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问题 选择题

图甲为某一质点作简谐振动的振动图象，图乙是t=0时刻某简谐横波的波形图，波的传播方向沿x轴正向。下列说法中正确的是（  ）

图甲                                       图乙

A．在甲图中，质点的振动周期为1s

B．在甲图中，t＝1s时，质点的速度方向沿y轴负向

C．在乙图中，横波的波长为2m

D．在乙图中，平衡位置为x=1m处的质点，此时刻的速度方向沿y轴负向

答案

BC

由甲图可知周期为2s，A错；乙图为波动图像，振动方向要向前看，根据“前代后，后跟前”可判断平衡位置为x=1m处的质点，此时刻的速度方向沿y轴正向，D错；

选择题

世界上降水最多的地区是（　　）

A．中纬度地区

B．南北回归线附近

C．赤道附近地区

D．两极地区
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问答题

Parents are required by law to see that their children receive full-time education, at school or elsewhere, between the ages of 5 and 16 in England, Scotland and Wales and 4 and 16 in Northern Ireland. About 93 percent of pupils receive free education from public funds, while the others attend independent schools financed by fees paid by parents. Many, aged 3-4 years, children attend nursery schools and classes (or, in England, reception classes in primary schools). Pre-school education may also be provided in some private day nurseries and pre-school playgroups (which are largely organized by parents). The Government has stated its commitment to a major expansion of pre-school education and wants all children to begin school with a basic foundation in literacy and numeracy. From September 1998 it is providing free nursery education in England and Wales for all 4 year olds whose parents want it, and is committed to staged targets for provision for 3 year olds thereafter. Local education authorities, in partnership with private and voluntary providers, have drawn up "early years development plans" for securing these objectives. The plans are designed to show how co-operation between private nurseries, playgroups and schools can best serve the interests of children and their parents. From April 1999, early years development partnerships and plans will be expanded to deliver quality childcare integrated with early education. In addition, the Government is working with local authorities and others in England to establish "early excellence centers" designed to demonstrate good practice in education and childcare. In Scotland, local education authorities have been taking the leading role, from August 1998, in planning and co-ordinating pre-school education and in providing places, working in partnership with voluntary and private providers. The Government planned to give all children in the pre-school year access to quality, part-time education by the winter of 1998. Northern Ireland has a lower compulsory school age of 4 and a single school entry date in September each year. A pre-school education expansion programme, undertaken through part-nership between the education and library boards, other statutory providers and the private and voluntary sectors, has provided additional pre-school places.
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