$\left[1\frac{1}{2}+1\frac{2}{3}\right]\xf7\left[\frac{6}{7}-\frac{5}{6}\right]=?$

$\frac{19}{180}$

$\frac{19}{252}$

$71\frac{1}{2}$

133

D. 133

$?=\left[\frac{3}{2}+\frac{5}{3}\right]\xf7\left[\frac{1}{42}\right]\phantom{\rule{0ex}{0ex}}=\frac{19}{6}\times 42\phantom{\rule{0ex}{0ex}}=133$