對營業線橋涵施工引起的線路加固工程， 施工單位在與（）簽訂施工安全協議后方可施工。
A、建設單位C
此題主要考察對營業線施工安全方面知識的掌握。營業線橋涵的施工要求是：營業線橋涵施工有關加固、防護不得入建筑限界。當對行車進行限速時，除應符合現行鐵路技術管理規程的規定外，必須制訂確保安全的措施，并應與設備管理單位簽訂協議后方可施工。根據以上要求，判定正確選項是“C.設備管理單位”
灰沼貍生活在南非，營集群生活。一些個體在群中其它個體取食時，占據高處放哨。放哨者通常第一個發現接近的捕食者，并且發出告警聲后，迅速到達安全的地方。研究者做了如下實驗：據上述現象及實驗，無法推斷出：
Chinesepeopleareverygoodattablet_____，andit'sourfavoritesport
()“Doyouwant_____orange?”“No，I'dlike_____bottleoforange.”
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.
()Iwouldlike________.
