\[\boxed{\text{676\ (676).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[\textbf{а)}\ (a - b)(a + b)\]
\[\textbf{б)}\ a^{2} + b^{2}\]
\(в)\ (a + b)^{2}\)
\[\textbf{г)}\ b^{2} - c^{2}\]
\[\textbf{д)}\ (b - c)^{3}\]
\[\textbf{е)}\ b^{3} + c^{3}\ \]