Решите примеры пожалуйста. Заранее спасибо .

Решите задачу:

$1) \: \sqrt{90 \times 30 \times 3} = \\ = \sqrt{9 \times 10 \times 3 \times 10 \times 3} = \\ = \sqrt{ {3}^{2} \times {10}^{2} \times {3}^{2} } = \\ = 3 \times 10 \times 3 = 90$
$2) \: \frac{6}{ {(2 \sqrt{3}) }^{2} } = \frac{6}{4 \times 3} = \frac{6}{12} = \frac{1}{2}$
$3) \: 5 \sqrt{11} \times 2 \sqrt{2} \times \sqrt{22} = \\ = 5 \times 2 \times \sqrt{11 \times 2 \times 22} = \\ = 10 \times \sqrt{11 \times 2 \times 11 \times 2} = \\ = 10 \times \sqrt{ {11}^{2} \times {2}^{2} } = \\ = 10 \times 11 \times 2 = \\ = 220$