#pragma comment(linker, "/STACK:1024000000,1024000000")
#include <iostream>
#include <string.h>
#include <stdio.h>
#include <vector>

using namespace std;
using namespace std;
const int maxn=50010;
vector<int> v[maxn],w[maxn],query[maxn],num[maxn];
int tt,n,m,dist[maxn],ans[maxn],fa[maxn];
bool vis[maxn];
void init()
{
    for(int i=1;i<=n;i++)
    {
        fa[i]=i;
        v[i].clear();
        w[i].clear();
        query[i].clear();
        num[i].clear();
        dist[i]=0;
        vis[i]=0;
        ans[i]=0;
    }
}
int find(int x)
{
    if(x!=fa[x])
        fa[x]=find(fa[x]);
    return fa[x];
}
void Union(int x,int y)
{
    int fx=find(x);
    int fy=find(y);
    if(fx!=fy)
        fa[fy]=fx;
}
void tarjan(int cur,int val)
{
    vis[cur]=1;
    dist[cur]=val;
    for(int i=0;i<v[cur].size();i++)
    {
        int temp=v[cur][i];
        if(vis[temp]) continue;
        tarjan(temp,val+w[cur][i]);
        Union(cur,temp);
    }
    for(int i=0;i<query[cur].size();i++)
    {
        int temp=query[cur][i];
        if(!vis[temp]) continue;
        ans[num[cur][i]]=dist[cur]+dist[temp]-2*dist[find(temp)];
    }
}
int main()
{
    int x,y,z;
    scanf("%d",&tt);
    while(tt--)
    {
        scanf("%d%d",&n,&m);
        init();
        for(int i=0;i<n-1;i++)
        {
            scanf("%d%d%d",&x,&y,&z);
            v[x].push_back(y);
            v[y].push_back(x);
            w[x].push_back(z);
            w[y].push_back(z);
        }
        for(int i=0;i<m;i++)
        {
            scanf("%d%d",&x,&y);
            query[x].push_back(y);
            query[y].push_back(x);
            num[x].push_back(i);
            num[y].push_back(i);
        }
        tarjan(1,0);
        for(int i=0;i<m;i++)
            printf("%d\n",ans[i]);
    }
    return 0;
}