b) [tex]\frac{2\sqrt{2}\cdot\sqrt{5}}{\sqrt{5}\cdot\sqrt{5}}=\frac{2\sqrt{2\cdot5}}{5}=\boxed{\frac{2\sqrt{10}}{5}}[/tex]
c) [tex]\frac{7\cdot\sqrt{3}}{4\sqrt{3}\cdot\sqrt{3}}=\frac{7\sqrt{3}}{4\cdot3}=\boxed{\frac{7\sqrt{3}}{12}}[/tex]
d) [tex]\frac{\sqrt{11}\cdot\sqrt{13}}{2\sqrt{13}\cdot\sqrt{13}}=\frac{\sqrt{143}}{2\cdot13}=\boxed{\frac{\sqrt{143}}{26}}[/tex]
