A.have learnt how to communicate in nonverbal language through books
B.can communicate in nonverbal language only when they are mature
C.have learnt how to communicate in nonverbal language since a child
D.communicate in nonverbal language much less than they do in verbal language

A.looking at the words that are written
B.understanding
C.saying something aloud
D.expressing

A.faces
B.legs
C.hands
D.stomachs

A.faces
B.legs
C.hands
D.stomachs

A.V (Vôn)
B.W (Oát)
C.A (Ampe)
D.V/m (Vôn/mét)

A.cùng pha nhau.
B.lệch pha nhau \(\frac{\pi }{4}\).
C.ngược pha nhau.
D.lệch pha nhau \(\frac{\pi }{2}\).

A.êlectron  
B.nơtron
C.pôzitron
D.prôtôn

A.2,11 eV.
B.4,22 eV.
C.0,42 eV.
D.0,21 eV.

A.\(\frac{E}{{{E_0}}} =  - \frac{B}{{{B_0}}}\)  
B.\(\frac{E}{{{E_0}}} = \frac{B}{{{B_0}}}\)
C.\({\left( {\frac{E}{{{E_0}}}} \right)^2} + {\left( {\frac{B}{{{B_0}}}} \right)^2} = 1\)
D.\({\left( {\frac{E}{{{E_0}}}} \right)^2} + {\left( {\frac{B}{{{B_0}}}} \right)^2} = 2\)

A.\(4\pi H{\rm{z}}\)
B.2Hz.
C.0,5 Hz.
D.4 Hz.