Răspuns:
[tex] \sqrt{900} - \sqrt{ {3}^{6} } + \sqrt{( { - 2)}^{4} } = \\ 30 - \sqrt{729} + \sqrt{16} = \\ 30 - 27 + 4 = \\ 3 + 4 = \\ = 7[/tex]
D. 7
Succes!!!