Заполни пропуски

Запиши произведения в виде степени:

1.  \(4\cdot 4\cdot 4\cdot 4=\) [ ];  
   

2.  \((1,3)\cdot (1,3)\cdot (1,3)=\) [ ];  
   

3.  \(\bigg(-\dfrac{2}{3}\bigg)\cdot \bigg(-\dfrac{2}{3}\bigg)\cdot \bigg(-\dfrac{2}{3}\bigg)\cdot {\bigg(-\dfrac{2}{3}\bigg)}=\) [ ];  
   

4.  \(\dfrac{a}{b}\cdot \dfrac{a}{b}\cdot \dfrac{a}{b}\cdot \dfrac{a}{b}\cdot \dfrac{a}{b}=\) [ ];  
   

5.  \(\underbrace{7\cdot 7\cdot...\cdot 7}\_{k\text{ раз}}=\) [ ];  
   

6.  \(\underbrace{(ab)\cdot (ab)\cdot...\cdot (ab)}\_{13\text{ раз}}=\) [ ].