#include<iostream>

#include<cstdio>

#include<cstring>

#include<vector>

#include<algorithm>

#define MAX_N 100005

#define MAX_D 22

using namespace std;

struct edge {

public:

    int to, cost;

    edge(int t, int c) : to(t), cost(c) { }

    edge() { }

};

vector<edge> G[MAX_N];

int n,q;

int ancestor[MAX_N][MAX_D];

int depth[MAX_N];

int dis[MAX_N];

void init(){

    memset(dis,,sizeof(dis));

    memset(ancestor,,sizeof(ancestor));

    memset(depth,,sizeof(depth));

    for(int i=;i<=n;i++)G[i].clear();

}

void dfs(int u,int p) {

    for (int i = ; i < G[u].size(); i++) {

        int v = G[u][i].to;

        if (v == p)continue;

        dis[v]=dis[u]+G[u][i].cost;

        depth[v] = depth[u] + ;

        ancestor[v][] = u;

        dfs(v, u);

    }

}

void getAncestor() {

    for (int j = ; j < MAX_D; j++)

        for (int i = ; i <= n; i++)

            ancestor[i][j] = ancestor[ancestor[i][j - ]][j - ];

}

int LCA(int u,int v) {

    if (depth[u] < depth[v])swap(u, v);

    for (int i = MAX_D - ; i >= ; i--) {

        if (depth[ancestor[u][i]] >= depth[v]) {

            u = ancestor[u][i];

            if (depth[u] == depth[v])break;

        }

    }

    if (u == v)return u;

    for (int i = MAX_D - ; i >= ; i--) {

        if (ancestor[u][i] != ancestor[v][i]) {

            u = ancestor[u][i];

            v = ancestor[v][i];

        }

    }

    return ancestor[u][];

}

int getDis(int u,int v) {

    int L = LCA(u, v);

    return dis[u] + dis[v] -  * dis[L];

}

int T;

int cas=;

int main() {

    cin >> T;

    while (T--) {

        printf("Case #%d:\n", ++cas);

        scanf("%d%d", &n, &q);

        init();

        for (int i = ; i < n - ; i++) {

            int u, v, c;

            scanf("%d%d%d", &u, &v, &c);

            G[u].push_back(edge(v, c));

            G[v].push_back(edge(u, c));

        }

        int x, y, z;

        scanf("%d%d%d", &x, &y, &z);

        dfs(, );

        getAncestor();

        while (q--) {

            int u, v;

            scanf("%d%d", &u, &v);

            int tmp, ans;

            ans = tmp = getDis(u, v);

            ans = min(ans, getDis(u, x) + getDis(y, v) + z);

            ans = min(ans, getDis(u, y) + getDis(x, v) + z);

            printf("%d\n", tmp - ans);

        }

    }

    return ;

}