A.25%.
B.50%.
C.75%.
D.20%.

A.8%.
B.10%.
C.9%.
D.11%.

A.Al.
B.Al2O3.
C.Al(OH)3.
D.AlCl3.

A.Etilen (CH2=CH2).
B.Ancol etylic (CH3CH2OH).
C.Etyl axetat (CH3COOC2H5).
D.Metylamin (CH3NH2).

A.\(\left\{ \begin{array}{l}x =  - \dfrac{1}{3}\\y =  - \dfrac{7}{3} + t\\z = \dfrac{{10}}{3}\end{array} \right.\)
B.\(\left\{ \begin{array}{l}x =  - \dfrac{1}{7}t\\y = 1 - \dfrac{7}{3}t\\z = \dfrac{{10}}{3}t\end{array} \right.\)
C.\(\left\{ \begin{array}{l}x = \dfrac{3}{7}t\\y = 1 - \dfrac{{25}}{7}t\\z = \dfrac{{18}}{7}t\end{array} \right.\)
D.\(\left\{ \begin{array}{l}x = \dfrac{3}{7}\\y =  - \dfrac{{25}}{7} + t\\z = \dfrac{{18}}{7}\end{array} \right.\)

A.\(494\)
B.\(484\)
C.\(474\)
D.\(464\)

A.\(\dfrac{7}{{32}}\)
B.\(\dfrac{1}{8}\)
C.\(\dfrac{3}{{32}}\)
D.\(\dfrac{5}{{16}}\)

A.\(60\pi {a^2}\)
B.\(15\pi {a^2}\)
C.\(75\pi {a^2}\)
D.\(80\pi {a^2}\)

A.\(4\)
B.\(2\)
C.\(1\)
D.\(3\)

A.\(\dfrac{\pi }{4}\)
B.\(\dfrac{\pi }{2}\)
C.\(\dfrac{{{\pi ^2}}}{4}\)
D.\(\dfrac{{{\pi ^2}}}{2}\)