Answer
Last two terms:
$25a^{26/3}$
$a^{25/3}$
Work Step by Step
We find the last 2 terms in the expansion of $(a^{2/3}+a^{1/3})^{25}$ by using Binomial Theorem coefficients:
$\left(\begin{array}{l}25\\24\end{array}\right)(a^{2/3})^1\cdot(a^{1/3})^{24}=25a^{2/3}a^{24/3}=25a^{26/3}$
$\left(\begin{array}{l} 25\\25\end{array}\right)(a^{1/3})^{25}=a^{25/3}$
