A.\(2i\)  
B.\(2,5i\)
C.\(i\)
D.\(1,5i\)

A.Tia \(\alpha \)  
B.Tia \(\gamma \)  
C.Tia\({\beta ^ + }\)
D.Tia \({\beta ^ - }\)

A.\({E_n} + {E_m}\)
B.\({n^2}{E_n} - {m^2}{E_m}\)
C.\({n^2}{E_n} + {m^2}{E_m}\)
D.\({E_n} - {E_m}\)

A.\(12,{56.10^{ - 4}}T\)   
B.\(6,{28.10^{ - 4}}T\)  
C.\({4.10^{ - 4}}T\)  
D.\({2.10^{ - 4}}T\)

A.that
B.when
C.which
D.where

A.appropriate
B.appropriately
C.appropriation
D.appropriating

A.slight
B.slighted
C.slightly
D.slightness

A.turning
B.raising
C.pointing
D.nodding

A.thoughtful
B.impolite
C.attentive
D.communicative

A.rude
B.slight
C.small
D.impolite