3. Simplify :    (i)     $2^{\frac{2}{3}}.2^{\frac{1}{5}}$

Given number is $2^{\frac{2}{3}}.2^{\frac{1}{5}}$
$\Rightarrow 2^{\frac{2}{3}}.2^{\frac{1}{5}} = 2^{\frac{2}{3}+\frac{1}{5}} = 2^{\frac{10+3}{15}} = 2^\frac{13}{15}$            $\left ( \because a^n.a^m = a^{n+m} \right )$
Therefore, the answer is $2^{\frac{13}{15}}$