A.\(a = 2\)
B.\(a = \dfrac{1}{{\sqrt 2 }}\)
C.\(a = \dfrac{1}{2}\)
D.\(a = \sqrt 2 \)

A.\(\left( { - 3;0} \right)\)
B.\(\left( {0;3} \right)\)
C.\(\left( {0; - 3} \right)\)
D.\(\left( {3;0} \right)\)

A.\(V = 12{a^3}\)
B.\(V = 2{a^3}\)
C.\(V = 4{a^3}\)
D.\(V = \dfrac{4}{3}{a^3}\)

A.\(\Delta :\,\,\left\{ \begin{array}{l}x = 1 - 4t\\y =  - 2 + 3t\\z = 2 - 2t\end{array} \right.\)
B.\(\Delta :\,\,\left\{ \begin{array}{l}x = 1 + 4t\\y =  - 2 - 3t\\z = 2 + 2t\end{array} \right.\)
C.\(\Delta :\,\,\left\{ \begin{array}{l}x =  - 4 + t\\y = 3 - 2t\\z =  - 2 + 2t\end{array} \right.\)
D.\(\Delta :\,\,\left\{ \begin{array}{l}x = 4 + t\\y =  - 3 - 2t\\z = 2 + 2t\end{array} \right.\)

A.\(\left( { - 1;0} \right)\)
B.\(\left( {0;1} \right)\)
C.\(\left( {2; + \infty } \right)\)
D.\(\left( {1;2} \right)\)

A.\( - 8\)
B.\(128\)
C.\( - 64\)
D.\(64\)

A.\({30^0}\)
B.\({120^0}\)
C.\({60^0}\)
D.\({90^0}\)

A.\(\dfrac{3}{2}\)
B.\(8\)
C.\(\dfrac{1}{8}\)
D.\(6\)

A.\({30^0}\)
B.\({90^0}\)
C.\({120^0}\)
D.\({60^0}\)

A.\(x = 6\)
B.\(x = 4\)
C.\(x = 7\)
D.\(x = 1\)