#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n);i++)
#define sz(x) int(x.size())
typedef long long ll;
typedef long double ld;
typedef pair<int,int> P;
typedef pair<ll, int> PL;
constexpr int INF = 2e9;

struct LowestCommonAncestor {
  int n, h;
  vector<vector<int>> par;
  vector<vector<pair<int,int>>> g;
  vector<int> dep;
  vector<int> weight;

  LowestCommonAncestor(int sz) {
    n = sz; h = 1;
    g.resize(n), dep.resize(n), weight.resize(n);
    while ((1 << h) <= n) h++;
    par.assign(h, vector<int>(n, -1));
  }

  void add_edge(int u, int v, int w = 0) {
    g[u].emplace_back(make_pair(v, w));
    g[v].emplace_back(make_pair(u, w));
  }

  void dfs(int u, int p, int depth) {
    par[0][u] = p;
    dep[u] = depth;
    if (p == -1) weight[u] = 0;
    for (auto v : g[u]) {
      if (v.first == p) continue;
      weight[v.first] = weight[u] + v.second;
      dfs(v.first, u, depth + 1);
    }
  }

  void build(int root = 0) {
    dfs(root, -1, 0);
    for (int i = 0; i + 1 < h; i++) {
      for (int j = 0; j < n; j++) {
        if (par[i][j] != -1) par[i+1][j] = par[i][par[i][j]];
        else par[i+1][j] = -1;
      }
    }
  }

  int query(int u, int v) {
    if (dep[u] > dep[v]) swap(u, v);
    for (int i = h-1; i >= 0; i--) {
      if ( ((dep[v] - dep[u]) >> i) & 1) v = par[i][v];
    }
    if (u == v) return u;
    for (int i = h-1; i >= 0; i--) {
      if (par[i][u] != par[i][v]) {
        u = par[i][u];
        v = par[i][v];
      }
    }
    return par[0][u];
  }

  int dist(int u, int v) {
    return dep[u] + dep[v] - 2 * dep[query(u, v)];
  }

  int weight_sum(int u, int v) {
    return weight[u] + weight[v] - 2 * weight[query(u, v)];
  }
};

int main() {
  int n;
  scanf("%d", &n);
  LowestCommonAncestor lca(n);

  rep(i,n-1) {
    int a, b, c;
    scanf("%d %d %d", &a, &b, &c);
    a--; b--;
    lca.add_edge(a, b, c);
  }

  lca.build();

  int q;
  scanf("%d", &q);
  while (q--) {

    int s, t;
    scanf("%d %d", &s, &t);
    s--; t--;

    printf("%d\n", lca.weight_sum(s, t));

  }
  return 0;
}