a)
[tex]2^6*5^7=2^5*2*5^5*5^2=(2*5)^5*2*5^2=10^5*2*25=50*10^5=5000000[/tex]
b)
[tex]0,4^4*5^7=0,2^4*5^4*5^3=(0,2*5)^4*5^3=1^4*5^3=1*125=125[/tex]
c)
[tex](\frac{2}{3})^6:(\frac{4}{9})^5=(\frac{2}{3})^5*\frac{2}{3}*(\frac{9}{4})^5=(\frac{2}{3}*\frac{9}{4})^5*\frac{2}{3} = (\frac{3}{2})^5*\frac{2}{3} = (\frac{3}{2})^5:\frac{3}{2}=(\frac{3}{2})^4=\frac{81}{16}=5\frac{1}{16}[/tex]
