The division of two irrational numbers is

1. a rational number
2. an irrational number
3. either a rational number or an irrational number
4. neither rational number nor irrational number

Which of the following is an irrational number

1. $\sqrt{\dfrac{4}{9}}$

2. $\dfrac{\sqrt{12}}{\sqrt{3}}$

3. $\sqrt{7}$

4. $\sqrt{81}$

Which of the following is an irrational number ?

1. 0.14
2. $0.14\overline{16}$
3. $0.\overline{1416}$
4. 0.4014001400014…

Which of the following numbers has non-terminating repeating decimal expansion ?

1. $\dfrac{11}{80}$

2. $\dfrac{17}{160}$

3. $\dfrac{63}{240}$

4. $\dfrac{93}{420}$