1. Use the resistance formula

For a conductor, $R = \rho \frac{L}{A}$ where:

• $\rho = 3 \times 10^{-7}\ \Omega\,\text{m}$
• $L$ = distance between the two opposite faces
• $A$ = area of cross-section perpendicular to current

2. Identify the relevant dimensions

The rectangular parallelopiped has dimensions: $1\text{ cm} \times 1\text{ cm} \times 100\text{ cm}$

The phrase "between its two opposite rectangular faces" refers to the two end faces of area $1\text{ cm} \times 1\text{ cm}$ so current flows along the length $L = 100\text{ cm} = 1\text{ m}$

Cross-sectional area: $A = 1\text{ cm} \times 1\text{ cm} = 1\text{ cm}^2 = 10^{-4}\text{ m}^2$

3. Substitute into the formula

$R = 3 \times 10^{-7} \times \frac{1}{10^{-4}}$

$R = 3 \times 10^{-7} \times 10^4$

$R = 3 \times 10^{-3}\ \Omega$

4. Match with the required format

The answer is asked in the form: $\underline{\hspace{2cm}} \times 10^{-7}\ \Omega$

So, $3 \times 10^{-3} = x \times 10^{-7}$

Thus, $x = 3 \times 10^4 = 30000$

5. Comparison with stored answer

My derived answer is $30000$, not $3$. The stored answer appears to have ignored the unit conversion from $\text{cm}^2$ to $\text{m}^2$ or misread the requested coefficient.