#include <stdio.h>
#include <stdlib.h>
#define SWAP(x,y,t) ((t)=(x),(x)=(y),(y)=(t))
int repeat=0;
int spotAmount=0;
int wayAmount=0;
int destAmount=0;
int ptFrom[4950]={};
int ptTo[4950]={};
int weight[4950]={};
int destPt[4950]={};
int temp=0;
typedef struct stor
{
    int sum;
    int step;
    int dir[4950];
}stor;
typedef struct link  //연결리스트 사용
{
    stor memoPt;
    struct link* next;
}link;

link* startLink=NULL;
link* lastLink=NULL;
int storAmount=0;

int partition(int list[],int left,int right)  //퀵정렬
{
    int pivot,temp;
    int low,high;
    low=left;
    high=right+1;
    pivot=list[left];
    do{
        do
        {
            low+=1;
        }while(low<=right&&list[low]<pivot);
        do
        {
            high-=1;
        }while(high>=left&&list[high]>pivot);
        if(low<high)
        {
            SWAP(list[low],list[high],temp);
            SWAP(ptTo[low],ptTo[high],temp);
            SWAP(weight[low],weight[high],temp);
        }
    }while(low<high);
    SWAP(list[left],list[high],temp);
    SWAP(ptTo[left],ptTo[high],temp);
    SWAP(weight[left],weight[high],temp);
    return high;
}
void quick_sort(int list[],int left,int right)  //퀵정렬
{
    if(left<right)
    {
        int q=partition(list,left,right);
        quick_sort(list,left,q-1);
        quick_sort(list,q+1,right);
    }
}

void func(int curNum,int loopNum,long long sum,stor memo) //재귀함수
{
    if(curNum==ptTo[wayAmount-1])
    {
        memo.dir[memo.step++]=curNum;
        memo.sum=sum;
        link* newLink=(link*)malloc(sizeof(link));  //메모리 할당하는 부분!!
        newLink->memoPt=memo;
        newLink->next=NULL;
        if(storAmount==0)
        {
            startLink=newLink;
            lastLink=newLink;
        }
        else
        {
            lastLink->next=newLink;
            lastLink=newLink;
        }
        storAmount++;
        return;
    }
    for(int i=loopNum+1;i<wayAmount;i++)
    {
        if(curNum==ptFrom[i])
        {
            stor tempMemo=memo;
            tempMemo.dir[(tempMemo.step)++]=curNum;
            func(ptTo[i],i,sum+weight[i],tempMemo);
            continue;
        }
        else if(curNum<ptFrom[i])
            break;
    }
}
int main()
{
    long long allWay=0;
    long long findNum=0;
    scanf("%d",&repeat);
    while(repeat--)
    {
        startLink=NULL;
        lastLink=NULL;
        storAmount=0;
        spotAmount=wayAmount=destAmount=0;
        scanf("%d %d %d",&spotAmount,&wayAmount,&destAmount);
        for(int i=0;i<wayAmount;i++)
        {
            scanf("%d %d %d",&ptFrom[i],&ptTo[i],&weight[i]);
            if(ptFrom[i]>ptTo[i])
            {
                temp=ptTo[i];
                ptTo[i]=ptFrom[i];
                ptFrom[i]=temp;
            }
        }
        for(int i=0;i<destAmount;i++)
            scanf("%d",&destPt[i]);

        quick_sort(ptFrom,0,wayAmount-1);

        stor memo;
        memo.sum=0;
        memo.step=1;
        memo.dir[0]=1;
        for(int i=0;ptFrom[0]==ptFrom[i];i++)
            func(ptTo[i],i,weight[i],memo);

        link* findLink=startLink;
        if(storAmount>0)
        {
            int min=startLink->memoPt.sum;
            for(;findLink->next!=NULL;)
            {
                if(min>findLink->memoPt.sum) min=findLink->memoPt.sum;
                findLink=findLink->next;
            }
            for(int k=0;k<destAmount;k++)
            {
                allWay=0;
                findNum=0;
                findLink=startLink;
                link* nextLink=startLink;
                for(;findLink->next!=NULL;)
                {
                    findLink=nextLink;
                    if(min==findLink->memoPt.sum)
                    {
                        allWay++;
                        for(int j=0;j<findLink->memoPt.step;j++)
                        {
                            if(findLink->memoPt.dir[j]==destPt[k])
                            {
                                findNum++;
                                break;
                            }
                        }
                    }
                    nextLink=findLink->next;
                }
                if(allWay==0||findNum==0)
                {
                    printf("0/1\n");
                    continue;
                }

                long long finalFindNum=findNum;
                long long finalAllWay=allWay;
                for(long long i=2;i<=finalFindNum;i++)
                {
                    if(finalFindNum%i==0&&finalAllWay%i==0)
                    {
                        finalFindNum/=i;
                        finalAllWay/=i;
                    }
                }
                findNum=finalFindNum;
                allWay=finalAllWay;

                printf("%lld/%lld\n",findNum,allWay);
            }
            link* nextLink=startLink;
            for(findLink=startLink;findLink!=NULL;)
            {
                nextLink=findLink->next;
                free(findLink);  //메모리 제거하는부분
                findLink=nextLink;
            }
        }
        else
        {
            printf("0/1\n");
            continue;
        }


    }

    return 0;
}