英语中的基数词和序数词的几道题

我已经写出来啦麻烦大家帮我写出答案并作出：“选择答案的理由解释”

1.itwilltakethem___________tofinishthetask

A.fouryearsandhalfBfourandhalfyears

CfourandahalfyearsDfouryearsofahalf

2.thestudentswereaskedtowritea_____compositionlastclass

Afour---hundreds----wordBfour-----hundred---word

Cfour----hundreds----wordsDfour----hundred----words

3.thegirlisin_______

AhertwentyBhertwentieth

ChertwentiesDhertwentys

4.whattimeisitit's______(2:55)

Afifty---fivepasttwoBtwopastfifty---five

CfivetotwoDfivetothree

5.heis_________inourclass

AthefourthtallestBfourthtallest

CthefourtallestDfourtallest

6.________starsaneinthesky

AthousandBthousandsof

CthousandofDathousands

7._________ischildren'sday

AfirstJuneBJunetheone

CJunethefirstDJunefirst

8.thereare_______studentsinourclass

AfortyBfourtyCfourthDforteen

9.thefirstworldwarbrokeout_________

Ainthe1910Batthe1910

Cinthe1910sDat1910

10.whichclassareyouinwearein__________

AtheclassoneB.classfirst

CclassoneD.firstclass