\[1)\ z = - 5 - 2\sqrt{6}i;\]
\[|z| = \sqrt{( - 5)^{2} + \left( - 2\sqrt{6} \right)^{2}} =\]
\[= \sqrt{25 + 24} = \sqrt{49} = 7.\]
\[2)\ z = - 9;\]
\[|z| = \sqrt{( - 9)^{2} + 0^{2}} = \sqrt{81 + 0} =\]
\[= \sqrt{81} = 9.\]
\[3)\ z = - i;\]
\[|z| = \sqrt{0^{2} + ( - 1)^{2}} = \sqrt{0 + 1} =\]
\[= \sqrt{1} = 1.\]
\[4)\ z = \cos\frac{\pi}{6} + i\sin\frac{\pi}{6};\]
\[|z| = \sqrt{\cos^{2}\frac{\pi}{6} + \sin^{2}\frac{\pi}{6}} = \sqrt{1} = 1.\]