Answer :

[tex]a)\ 0.14 = \frac{14}{100}\ (rational)\\\\ b)\ \frac{1}{3}\ (rational)\\\\ c)\ \sqrt{4} = \sqrt{2^2}=\frac{2}{1}\ (rational)\\\\ d)\ \sqrt{6} = 2.4494897427...\ (irrational)[/tex]