题目内容：
根据下面资料，回答题 Pay and productivity, it is generally assumed, should be related．But the relationship seems toweaken (21)_________ people get older．Mental ability declines with age．That is the same for the brainy and the dim--and not(22)_________ for humans: it is measurable even for fruit flies．(23) _________minds that keeplively will suffer less than the lazy．In general, the more education you have, the more productiveyour old (24) _________will be．Some (25) _________decline faster than others．According to most studies, people' s numerical and reasoning abilities are at their best in their 20s and early 30s．(26) _________abilitiesthose that depend on knowledge--may improve with age．
For most workers, decreased abilities will (27) _________to lower productivity; only a minority will find know-how and knowledge outweighs their falling powers．Even those employees whoremain highly productive will be likely to shine only in a narrow (28)_________
Academics notice this．It is less clear that employers do．Studies of supervisors-ratings showno clear correlation (29) age and perceived productivity．When other employees-viewsare (30) _________into account though, the picture changes: these ratings suggest that workers intheir 30s are the (31)_________ productive and hardworking, with scores falling thereafter．
That is (32) _________up by studies of work samples, which find lower productivity amongthe oldest employees．A study for America' s Department of Labor showed job performance peaking at 35and (33)_________ declining．It varied by industry: the fall was slower in footwear,but faster in furniture．
Intellectual occupations are harder to measure, but the picture is the same．Academics seem topublish (34) _________as they age．Painters, musicians and writers show the same tendency．Their output peaks in their 30s and 40s．The only (35) _________is female writers, who are mostproductive in their 50s．
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