a. √81/49=7/3∈Q
c. √2,25=√225/100=√9/4=3/2∈Q
d. √0,(11)=√11/99=√1/9=1/3∈Q
e. √5 4/9=√49/9=7/3∈Q
f. √1,36(1)=√(1361-136)/900=√1225/900=√49/36=7/6∈Q
