=>\(B=\left(2\cdot\frac{1}{547}\cdot\frac{3}{211}\right)-\left(\frac{546}{547}\cdot\frac{1}{211}\right)-\left(\frac{4}{547\cdot211}\right)\)
=>\(B=\frac{6}{547\cdot211}-\frac{546}{547\cdot211}-\frac{4}{547\cdot211}\)
=>\(B=\frac{6}{115417}-\frac{546}{115417}-\frac{4}{115417}\)
=>\(B=\frac{-544}{115417}\)