842 (а,б) помогите срочно надо

А) $-3 \frac{1}{5}*(- \frac{1}{4})^{2}=- \frac{16}{5}* \frac{1}{16}=- \frac{16}{80}=- \frac{1*16}{5*16}=- \frac{1}{5}$

б) $-8 \frac{2}{3}* (-\frac{1}{26}):(- \frac{7}{9})^{2} \\ \\ -8\frac{2}{3}*(- \frac{1}{26})=- \frac{26}{3}*(- \frac{1}{26})= \frac{26}{78}= \frac{1*26}{3*26}= \frac{1}{3} \\ \\ \frac{1}{3}:(- \frac{7}{9})^{2}= \frac{1}{3}: \frac{49}{81}= \frac{1}{3}* \frac{81}{49}= \frac{81}{147}= \frac{27*3}{49*3}= \frac{27}{49}$