A.\(\pi ra{\rm{d}}/s\)
B.\(2\pi ra{\rm{d}}/s\)
C.\(5cm/s\)
D.\(0{\rm{r}}a{\rm{d}}/s\)

A.\(\frac{1}{{2\pi }}.\sqrt {\frac{\ell }{g}} .\)
B.\(2\pi \sqrt {\frac{\ell }{g}} .\)
C.\(\frac{1}{{2\pi }}.\sqrt {\frac{g}{\ell }} .\)
D.\(2\pi \sqrt {\frac{g}{\ell }} .\)

A.\({q_0} = {I_0}\omega \)
B.\({q_0} = \frac{\omega }{{{I_0}}}\)
C.\({q_0} = \frac{{{I_0}}}{\omega }\)
D.\({q_0} = {I_0}{\omega ^2}\)

A.\(40\Omega \)
B.\(10\Omega \)
C.\(50\Omega \)
D.\(20\Omega \)

A.\(U = 84 \pm 1,4\left( V \right).\)
B.\(U = 84 \pm 2,0\left( V \right).\)
C.\(U = 60,0 \pm 1,4\left( V \right).\)
D.\(U = 60,0 \pm 2,0\left( V \right).\)

A.Al3+.
B.Mg2+.
C.Ag+.
D.Na+.

A.tính axit.
B.tính bazơ.
C.tính oxi hóa.
D.tính khử.

A.Al.
B.Fe.
C.Na.
D.Ag.

A.Na.
B.K.
C.Hg.
D.Cs.

A.Vinh.
B.Đà Nẵng.
C.Quy Nhơn.
D.Nha Trang..