To determine the cell constant, we need to use the following relationship between specific conductivity (or conductivity), resistance, and the cell constant:
\(k = \frac{1}{R} \times K\)
Where:
Given in the problem:
Substitute these values into the equation:
\(0.0129 = \frac{1}{100} \times K\)
Rearrange the equation to solve for \(K\):
\(K = 0.0129 \times 100\)
Calculate the value of \(K\):
\(K = 1.29\)
Therefore, the cell constant of the cell is 1.29.
Conclusion: The correct answer is 1.29, so option 2 is the correct choice.