\[\boxed{\text{675\ (675).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[\textbf{а)}\ b - a = - (a - b) = - 0,5\]
\[\textbf{б)}\ \frac{1}{b - a} = \frac{1}{- (a - b)} = - \frac{1}{0,5} =\]
\[= - 2\]
\[\textbf{в)}\ (a - b)^{2} = {0,5}^{2} = 0,25\]
\[\textbf{г)}\ (b - a)^{2} = \left( - (a - b) \right)^{2} =\]
\[= ( - 0,5)^{2} = 0,25\]
\[\textbf{д)}\ (a - b)^{3} = (0,5)^{3} = 0,125\]
\[\textbf{е)}\ \ (b - a)^{3} = \left( - (a - b) \right)^{3} =\]
\[= ( - 0,5)^{3} = - 0,125\]