Why didn’t people begin to use unmanned vehicles in undersea exploration until r

游客2023-10-06 53

问题 Why didn’t people begin to use unmanned vehicles in undersea exploration until recently?
It is because of the ______.
[br] What does the author mean by saying "more challenging" in the last paragraph?

选项

答案 More demanding

解析

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Why didn’t people begin to use unmanned vehicles in undersea exploration until r

Fewpeoplecan______themorningexerciseseveryday.A、insisttoB、goonC、wipe

Peoplegenerallycalleachotherbytheir(11)muchsoonerintheiracquaintance

Peoplegenerallycalleachotherbytheir(11)muchsoonerintheiracquaintance

TheRedCrossisaninternationalorganizationwhichcaresforpeoplewhoare

Themiddlepartofthe20thcenturybroughtnewwaystohelppeoplegetoverdis

Thepassagestatesthatpeoplefromvariouscultures______.[br]Generallyhost

Thepassagestatesthatpeoplefromvariouscultures______.[br]Accordingtot

Thepassagestatesthatpeoplefromvariouscultures______.[br]Inthethirds

Georgeisoneofthosepeoplewho______troubleinworkingoutthisproblem.A、h

Whenpeoplebecomegoodatdoingthethingstheyliketheyfindthemselves.

TheGherkinBuildingCommissionedby:【L31】________firmcalledFosterandPartner

[audioFiles]audio_eusm_j01_302(20099)[/audioFiles]A、Putastampontheletter.

HowtoReinventCollegeRankings:ShowtheDataStudentsNeedMostA)A

()通常应成对使用。A.深沟球轴承 B.圆锥滚子轴承 C.推力球轴承 D.

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对于某水利施工企业而言，现有两套可供选择的机械。A套机械：投资10000万元

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