$-8\cdot\left(-7\right)$  

(a)  

 $-2,3\cdot\left(-2\right)$  

(a)  

 $\frac{6}{7}\cdot\left(-\frac{4}{7}\right)$  

(a)  

 $-\frac{4}{7}\cdot\frac{7}{9}$  

(a)  

 $\left(-7\right)^2$  

(a)  

 $-\left(2\right)^2$  

(a)  

 $\left(-2\right)^3$  

(a)  

 $3,18\cdot7,8+3,18\cdot2,2$  

(a)  

 $73\cdot\frac{4}{9}+73\cdot\frac{5}{9}$  

(a)