Let \(M\) denote the set of all real matrices of order 3 x 3 and let \(S = \{-3, -2, -1, 1, 2\}\). Let
\[
S_1 = \{A = [a_{ij}] \in M : A = A^T \text{ and } a_{ij} \in S, \forall i, j\},
\]
\[
S_2 = \{A = [a_{ij}] \in M : A = -A^T \text{ and } a_{ij} \in S, \forall i, j\},
\]
\[
S_3 = \{A = [a_{ij}] \in M : a_{11} + a_{22} + a_{33} = 0 \text{ and } a_{ij} \in S, \forall i, j\}.
\]
If \(n(S_1 \cup S_2 \cup S_3) = 125\), then \(\alpha\) equals: