A.\(\sqrt {20} \)
B.\(\sqrt {20}  + \sqrt {34} \).
C.\(\sqrt {34} \)
D.\(\sqrt {34}  - \sqrt {20} \)

A.\(7\)
B.\(19\)
C.\(21\)
D.\(38\)

A.\(\dfrac{{\pi {a^2}}}{{\sqrt 3 }}\)
B.\(\dfrac{{2\pi {a^2}}}{{\sqrt 3 }}\). 
C.\(4\pi {a^2}\).
D.\(2\sqrt 3 \pi {a^2}\).

A.\(\sqrt 3 \).
B.\(3\)
C.\(5\)
D.\(\sqrt 5 \).

A.\(27\).
B.\(5\).
C.\(20\).
D.\(23\).

A.\(2\)
B.\(6\).
C.\(4\).
D.\(3\).

A.A. \((7;1)\).   
B.B.  \((0;7)\).
C.C.  \((5;1)\).
D.D.  \((7;0)\).

A.0
B.1
C.2
D.3

A.A. \({u_5} = \dfrac{{ - 27}}{{16}}.\)   
B.B.  \({u_5} = \dfrac{{ - 16}}{{27}}.\)
C.C.  \({u_5} = \dfrac{{16}}{{27}}.\)
D.D.  \({u_5} = \dfrac{{27}}{{16}}.\)

A.A. \(7\).  
B.B.  \(10\).
C.C.  \(14\).
D. D.  \(6\).