The multiplicative inverse of $(8^0 + 5^0)(8^0 - 5^0)$ is:

1. 0

2. 49

3. 1

4. undefined

The value of $\Big[\Big(\dfrac{1}{4}\Big)^{-2} + \Big(\dfrac{1}{3}\Big)^{-2}\Big] ÷ \Big(\dfrac{1}{5}\Big)^{-2}$ is:

1. $\dfrac{1}{25}$

2. 1

3. 0

4. 625

If $\Big(\dfrac{5}{6}\Big)^5 \times \Big(\dfrac{6}{5}\Big)^{-4} = \Big(\dfrac{5}{6}\Big)^{3x}$, then the value of $x$ is:

1. $\dfrac{1}{3}$

2. $\dfrac{20}{3}$

3. -3

4. 3

$\Big(\dfrac{2}{5}\Big)^{-8} ÷ \Big(\dfrac{2}{5}\Big)^5$ is equal to:

1. $\Big(\dfrac{2}{5}\Big)^{-3}$

2. $\Big(\dfrac{2}{5}\Big)^{-13}$

3. $\Big(\dfrac{2}{5}\Big)^{13}$

4. $\Big(\dfrac{5}{2}\Big)^{-13}$