【单选题】某一反应的活化能为 65KJ · mol -1 ,则其逆反应的活化能为
【单选题】( )(改编)Stephen often practices English________ chatting with his American friend.
【单选题】Stephen: I want to send this package parcel post, registered. Clerk: ______ ? Stephen: Yes, please, for sixty dollars.
A.
Do you want it guaranteed
B.
Do you want it insured
C.
Do you want it preserved
D.
Do you want it ensured
【单选题】(改编题)Stephen often practices English________ chatting with his American friend.
【单选题】Stephen often practices English_____ chatting with his American friend.
【简答题】______ she first heard of the man referred to as a specialist. A) That was from Stephen B) It was Stephen whom C) It was from Stephen that D) It was Stephen that