[tex]I.~~2\sqrt{5} +\sqrt{5} =3\sqrt{5} ~~~~~~~~I.=D\\\\II.~~\sqrt{5\cdot 9} =\sqrt{5\cdot 3^{2} } =3\sqrt{5} ~~~~~~~~II.=D\\\\III.~~\sqrt{9-4} =\sqrt{5} ~~~~~~~~III.=A\\\\IV.~~\sqrt{3} \cdot \sqrt{15} =\sqrt{3\cdot 15} =\sqrt{45} =\sqrt{5\cdot 9} =\sqrt{5\cdot 3^{2} } =3\sqrt{5} ~~~~~~~~IV=D\\\\V.~~\sqrt{3+15} =\sqrt{18} =\sqrt{2\cdot 9} =\sqrt{2\cdot 3^{2} } =3\sqrt{2} ~~~~~~~~V=E\\\\VI.~~\sqrt{9} +\sqrt{1} =\sqrt{3^{2} } +\sqrt{1^{2} }=3+1=4~~~~~~~~VI=C[/tex]
