#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int, int>


void solve() {
    int n, m;
    cin >> n >> m;
    vector e(n + 1, vector<pii>());
    for (int i = 1, u, v, w; i < n; i++) {
        cin >> u >> v >> w;
        e[u].push_back({v, w});
        e[v].push_back({u, w});
    }

    vector<int> dep(n + 1), len(n + 1);
    int M = __lg(n);
    vector f(n + 1, vector<int>(M + 1));

    auto dfs = [&] (auto &&self, int u, int fa)->void {
        for (auto [v, w] : e[u]) {
            if (v == fa) continue;
            dep[v] = dep[u] + 1;
            len[v] = len[u] + w;
            f[v][0] = u;
            self(self, v, u);
        }
    };
    dfs(dfs, 1, 0);
    for (int j = 1; j <= M; j++) {
        for (int i = 1; i <= n; i++) {
            f[i][j] = f[f[i][j - 1]][j - 1];
        }
    }

    auto lca = [&] (int x, int y)->int {
        if (dep[x] < dep[y]) swap(x, y);
        int len = dep[x] - dep[y];
        for (int j = 0; j <= M; j++) {
            if (len >> j & 1) {
                x = f[x][j];
            }
        }
        assert(dep[x] == dep[y]);
        if (x == y) return x;

        for (int j = M; j >= 0; j--) {
            int nx = f[x][j], ny = f[y][j];
            if (nx == ny) continue;
            x = nx, y = ny;
        }
        return f[x][0];
    };
    while (m--) {
        int x, y;
        cin >> x >> y;
        // cout << " x = " << x << " y = " << y << endl;
        int l = lca(x, y);
        // cout << "lca = " << l << endl;
        cout << len[x] - len[l] + (len[y] - len[l]) << '\n';
    }
}
signed main() {
    ios::sync_with_stdio(0); cin.tie(0);
    int t = 1;
    cin >> t;
    while (t--) solve();
    return 0;
}
/*
g++ -std=c++20 1.cpp -o 1 && 1 < in.txt > out.txt
*/