Resposta:

b) 5/6

Explicação passo a passo:

[tex]\frac{2}{3} \div \frac{4}{5} \\\\ \frac{2\times5}{3\times 4} \\\\ \frac{10}{12} \\\\\frac{10\div2}{12\div2} \\\\ \bold{\frac{5}{6} }[/tex]