艺术学类近5年考研国家线的变化趋势是怎样的，本文告诉你！

首次以《名例律》作为封建成文法典总则的法典是（　　）。
A.《曹魏律》
B.《晋律》
C.《北齐律》
D.《唐律疏议》

Text 2 Britain's flexible labour market was a boon during the economic slump,helping keep joblessness down and then,when the recovery began,allowing employment to rise.Yet one of its bendier bits is causing politicians to fret.Ed Miliband,the leader of the Labour Party,has promised a crackdown on"zero-hours contracts"if he wins the next election.The government has launched a con8ultation.Zero-hours contracts allow finns to employ workers for as few or as many hours as they need,with no prior notice.In theory,at least,people can refuse work.Fully l.4m jobs were based on these contracts in January 2014,according to the Office for National Statistics.That is just 4%of the total,but the share rises to a quarter in the hospitality business.The contracts are useful for finns with unstable pattems of demand,such as hotels and restauranLs.Ihey have also helped firms to expand during the recovery-allowing them to test new business lines before hiring permanem stafir,who would be more costly to make redundani if things went wrong.Flexibility suits some workers,too.According to one survey,47%of those employed on zerohours conUacts were content to have no nunimum contracted hours.Many of these workers are in full-time education.The ability to tum down work is important to students,who want to revise at this time of year.Pensioners keen for a liLtle extra income can often live with the uncertainty of not having guaranteed hours.Yet that leaves more than a quarter of workers on zero-hours contracts who say they are unhappy wirh their condirions.Some of this is cyclical.During recessions,a dearth of permanent positions forces people into jobs with no contracted hours even if they do not want them.Underemployment is pfuticularly prevalent among these workers,35%of whom would like more hours compared with 12qo in offier jobs.As the economy recovers,many should be able to renegotiate their contracts or find permanent jobs.But the recovery will not cause unwanted zero-hours contracts to disappear.Some workers will never have much negoLiating power:they are constrained by geography,family commitments and lack of competition for their skills among a small number of big employers.Zero-hours contracts make it easier for employers to abuse their labour-market power.Some use them to avoid statutory obligations such as sick and matenuty pay.Workers are penalised for not being available when requested.And some contracts contain exclusivity clauses which prevent workers from taking additional jobs.These can harm other employers as well as workers,and actually reduce labour market flexibility.That,at least,is worth doing away with.
Who may not be satisfied wiLh zero-hours contracts?

A.People with specific goals.
B.Workers requiring flexibility.
C.Students doing part-time jobs.
D.Pensioners desiring more income.

设总体X～N（μ,σ^2）,X1,X2,…,Xn为总体X的简单随机样本,X与S^2分别为样本均值与样本方差,则().