a)
[tex]-(-1\frac{5}{6}*(-0,3))=-(-\frac{11}{6}*(-\frac{3}{10}))=-(\frac{11}{2}*\frac{1}{10})=-\frac{11}{20}[/tex]
b)
[tex]\frac{3^{4}*9^{4} }{9^{5}:27^{2} } :81=\frac{3^{4}*9^{4} }{3^{10}:3^{6} }*\frac{1}{81}=\frac{3^{4}*9^{4} }{3^4 } *\frac{1}{9^{2} }=9^{2}=81[/tex]
