电视监控系统图像质量主观评价水平分为5级，验收标准要求应不低于（）级。
A、2C
暂无解析
Howmany_____(hour)arethereinaday?
用竖式计算
(1)9.5÷0.05=
(2)1.7÷2.5=
(3)7÷1.4=
(4)26.26÷26=
JackisateacherofEnglish.Heisnotyoung，butheisnotold.Hehasaroundfaceandblackhair.Heistall.Therearefiftystudentsinhisclass.Theyalllikehim.Nowit'sintheafternoon.Look，somestudentsareworkingintheclassroom.Jackisthere，too.HeishelpingthemtostudyEnglish.Heisagoodteacher，andheisagoodfriendofthemall.
()1.WhatdoesJackdo?
A.Heisaworker.
B.Heisateacher.
C.Heisadoctor.
D.He'sanurse.
()2.Whatcolourishishair?
A.It'sblack.
B.Hisheiriswhite.
C.Itisbrown.
D.Hehasyellowhair.
()3.Howmanystudentsarethereinhisclass?
A.Therearefifteenstudentsinhisclass.
B.There'sfifty.
C.Hehasfifty.
D.There'refiftyinit.
()4.Jackisagoodteacher，isn'the?
A.Yes，heisn't.
B.No，heis.
C.Yes，he's.
D.Yes，heis.
()5.Whatarethestudentsdoingintheclassroom?
A.Theyarewalkingthere.
B.Theyaredoingtheirlessons.
C.Theyarehelpingtheirteacher.
两人进行踢毽子比赛，用抛硬币的方法来决定谁先踢是公平的。()
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