Four rational numbers p, q, r and s are such that q is the reciprocal of p and s is the reciprocal of r. The value of the expression $\Big([p + \dfrac{1}{q}] ÷ [r + \dfrac{1}{s}]\Big) ÷ \Big([s + \dfrac{1}{r}] ÷ [q + \dfrac{1}{p}]\Big)$ is equal to:

1. 1

2. 0

3. pr

4. $\dfrac{s}{q}$

$0.6 + 0.\overline{7} + 0.4\overline{7}$ is equal to:

1. $\dfrac{155}{90}$

2. $\dfrac{147}{90}$

3. $\dfrac{167}{90}$

4. none of these

$1.\overline{9} - 1.9$ is equal to :

1. 0

2. 1

3. 0.09

4. 0.1

When written in decimal form, which of the following will be a non-terminating and non-repeating number?

1. $1^{1/9}$

2. $2^{1/9}$

3. $2^{-9}$

4. $9^{1/2}$