2. For any subset $A(|A|>1)$ of $X_{n}=\{1,2, \cdots, n\}$, let the sum of the products of every two elements in $A$ be $f(A)$, the sum of the sums of every two elements in $A$ be $g(A)$, and the sum of the absolute values of the differences of every two elements in $A$ be $h(A)$. Find $\sum_{A \leq X_{n}} f(A), \sum_{A \leq X_{n}} g(A), \sum_{A \leq X_{n}} h(A)$.
$\begin{array}{l}\text { (Hint: } \sum_{1 \leq x_{n}} f(A)=2^{n-2} \sum_{1 \leqslant i<j \leqslant n} i j \\ =2^{n-5} \cdot \frac{n(n+1)(3 n+2)(n-1)}{3}, \\ \sum_{1 \leq x_{n}} g(A)=2^{n-2} \sum_{1<i<j<n}(i+j)=2^{n-3} n\left(n^{2}-1\right), \\ \left.\sum_{1 \leq x_{n}} h(A)=2^{n-2} \sum_{1<i<j<n}|i-j|=2^{n-2} C_{n+1}^{3} \cdot\right)\end{array}$