Statement I is correct: For diamagnetic substances, the magnetic susceptibility \( X \) lies between \( -1 \leq X < 0 \), as diamagnetic substances are repelled by the magnetic field, and their susceptibility is negative.
Statement II is also correct: Diamagnetic substances move from stronger magnetic fields to weaker magnetic fields due to their negative susceptibility. This is because diamagnetic materials tend to create an opposing magnetic field that repels the external field, thus moving to areas where the magnetic field is weaker.
Therefore, both statements are correct.

An infinite wire has a circular bend of radius \( a \), and carrying a current \( I \) as shown in the figure. The magnitude of the magnetic field at the origin \( O \) of the arc is given by:

Let \( a \in \mathbb{R} \) and \( A \) be a matrix of order \( 3 \times 3 \) such that \( \det(A) = -4 \) and \[ A + I = \begin{bmatrix} 1 & a & 1 \\ 2 & 1 & 0 \\ a & 1 & 2 \end{bmatrix} \] where \( I \) is the identity matrix of order \( 3 \times 3 \).
If \( \det\left( (a + 1) \cdot \text{adj}\left( (a - 1) A \right) \right) \) is \( 2^m 3^n \), \( m, n \in \{ 0, 1, 2, \dots, 20 \} \), then \( m + n \) is equal to: