#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cstdlib>
#include <cmath>
#include <set>
#include <map>
#include <vector>
#include <iostream>
#include <queue>
#define LL long long
#define pii pair <LL, int>
#define piii pair <int, pii>
#define xx first
#define yy second
//#define ls rt << 1
//#define rs rt << 1 | 1
#define lson ls, l, m
#define rson rs, m + 1, r
#define pdi pair <double, int>

using namespace std;

const int N = 110000, mod = 1e9 + 7;

int T[N], num[N], san[N], ls[N*20], rs[N*20], sum[N*20], l[N], r[N], a[N];
pii res[N];
int tot,rt, nn, cc;
//int n, m;

inline int read()
{
    int x=0,f=1;char ch=getchar();
    while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
    while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
    return x*f;
}

int head[N];

struct edge {
    int v, nx;
    edge (int v = 0, int nx = 0) : v (v) , nx (nx) {}
} e[N * 2];

void add (int u, int v) {
//    cout <<u << ' ' << v << endl;
    e[cc] = edge (v, head[u]);
    head[u] = cc++;
}

int sz[N];

int dfs (int u, int fa) {
//    cout << "  " << u << ' ' << fa << endl;
    sz[u] = 1;
    l[u] = ++nn;
    num[nn] = san[nn] = a[u];
    for (int i = head[u]; ~i; i = e[i].nx) {
        int v = e[i].v;
        if (v == fa) continue;
        dfs (v, u);
        sz[u] += sz[v];
    }
    r[u] = nn;
}

void Build(int l,int r,int &rt)
{
    rt=++tot;
    sum[rt]=0;
    if(l==r) return ;
    int m=(l+r)>>1;
    Build(l,m,ls[rt]);
    Build(m+1,r,rs[rt]);
}

void Update(int last,int p,int l,int r,int &rt)
{
    rt=++tot;
    ls[rt]=ls[last];
    rs[rt]=rs[last];
    sum[rt]=sum[last]+1;
    if(l==r) return ;
    int m=(l+r)>>1;
    if(p<=m) Update(ls[last],p,l,m,ls[rt]);
    else     Update(rs[last],p,m+1,r,rs[rt]);
}

int Query(int ss,int tt,int l,int r,int k)
{
    if(l==r) return l;
    int m=(l+r)>>1;
    int cnt=sum[ls[tt]]-sum[ls[ss]];
    if(k<=cnt)
        return Query(ls[ss],ls[tt],l,m,k);
    else
        return Query(rs[ss],rs[tt],m+1,r,k-cnt);
}

void gogogo()
{
//    int l,r,k;
//    for(int i=1;i<=n;i++)
//    {
//        scanf("%d",&num[i]);
//        san[i]=num[i];
//    }
    tot=0;
    sort(san+1,san+nn+1);
//    for (int i = 1; i <= nn; i++) cout << san[i] << endl;
    int cnt=std::unique(san+1,san+nn+1)-san-1;
    Build(1,cnt,T[0]);
    for(int i=1;i<=nn;i++)   num[i]=std::lower_bound(san+1,san+cnt+1,num[i])-san;
    for(int i=1;i<=nn;i++)    Update(T[i-1],num[i],1,cnt,T[i]);
    for (int i = 1; i <= nn; i++) {
        if (sz[i] & 1) res[i] = pii (san[Query(T[l[i]-1],T[r[i]],1,cnt,sz[i] / 2 + 1 )], 0);
        else {
            int tmp = san[Query(T[l[i]-1],T[r[i]],1,cnt,sz[i] / 2)] + san[Query(T[l[i]-1],T[r[i]],1,cnt,sz[i] / 2 + 1 )];
            res[i] = pii (tmp / 2, tmp & 1);
        }
    }
//    while(m--)
//    {
//        scanf("%d%d%d",&l,&r,&k);
//        int id=Query(T[l-1],T[r],1,cnt,k);
//        printf("%d\n",san[id]);
//    }
}

int main () {
//    freopen ("in.txt", "r", stdin);
    int T;
    cin >> T;
    while (T--) {
        int n, m, u, v, x;
        cin >> n >> m;
        cc = nn = 0;
        for (int i = 1; i <= n; i++) {
            a[i] = read ();
        }
        memset (head, -1, sizeof head);
        tot = 0;
        for (int i = 1; i < n; i++) {
            u = read ();
            v = read ();
//            cout << u << ' ' << v << endl;
            add (u, v);
            add (v, u);
        }
        dfs (1, 0);
        gogogo ();
        pii ans = pii (0, 0);
        while (m--) {
            x = read ();
            ans.xx *= 10;
            if (ans.yy) ans.yy = 0, ans.xx += 5;
//            cout << res[x].xx << ' ' << res[x].yy << endl;
            ans.xx += res[x].xx;
            ans.yy += res[x].yy;
            ans.xx %= mod;
        }
        cout << ans.xx;
        if (ans.yy) cout << ".5";
        else cout << ".0";
        cout << endl;
    }
}