/*
离线算法，LCATarjan
复杂度O(n+Q);
*/
#include<iostream>
#include<stdio.h>
#include<string.h>
using namespace std;const int MAXN=40005;
const int MAXQ=205;//查询数的最大值int dis[MAXN];//到根节点的距离//并查集部分
int F[MAXN];//需要初始化为-1
int find(int x){if(F[x]==-1)return x;return F[x]=find(F[x]);
}
void bing(int u,int v){int t1=find(u);int t2=find(v);if(t1!=t2)F[t1]=t2;
}
//***********************
bool vis[MAXN];//访问标记
int ancestor[MAXN];//祖先
struct Edge{int to,next;int d;
}edge[MAXN*2];
int head[MAXN],tot;
void addedge(int u,int v,int d){edge[tot].to=v;edge[tot].d=d;edge[tot].next=head[u];head[u]=tot++;
}struct Query{int q,next;int index;//查询编号
}query[MAXQ*2];
int answer[MAXQ];//存储最后的查询结果，下标0 Q-1
int h[MAXN];//注意此处为MAXN...
int tt;void add_query(int u,int v,int index){query[tt].q=v;query[tt].next=h[u];query[tt].index=index;h[u]=tt++;query[tt].q=u;query[tt].next=h[v];query[tt].index=index;h[v]=tt++;
}void init(){tot=0;memset(head,-1,sizeof(head));tt=0;memset(h,-1,sizeof(h));memset(vis,false,sizeof(vis));memset(F,-1,sizeof(F));memset(ancestor,0,sizeof(ancestor));
}
void LCA(int u){ancestor[u]=u;vis[u]=true;for(int i=head[u];i!=-1;i=edge[i].next){int v=edge[i].to;if(vis[v])continue;dis[v]=dis[u]+edge[i].d;LCA(v);bing(u,v);ancestor[find(u)]=u;}for(int i=h[u];i!=-1;i=query[i].next){int v=query[i].q;if(vis[v]){answer[query[i].index]=ancestor[find(v)];}}
}int main(){int T;int n,m;int i;int u,v,d;scanf("%d",&T);while(T--){init();scanf("%d%d",&n,&m);for(i=0;i<n-1;++i){scanf("%d%d%d",&u,&v,&d);addedge(u,v,d);addedge(v,u,d);}for(i=0;i<m;++i){scanf("%d%d",&u,&v);add_query(u,v,i);}dis[1]=0;LCA(1);for(i=0;i<m;++i){printf("%d\n",dis[query[i*2].q]+dis[query[i*2+1].q]-2*dis[answer[i]]);}}return 0;
}