已知t6=1.5s，t2=1.5s，t5=1s，t3=2s，则需要安装方向元件的是（ ） 

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69493' and id < 4501536 and id<>'4501536' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69493' and id > 4501536 and id<>'4501536' order by id asc limit 5