#include <bits/stdc++.h>
#define LL long long
using namespace std;
template <typename T> void read(T &x){
    x = 0; int f = 1; char ch = getchar();
    while (!isdigit(ch)) {if (ch == '-') f = -1; ch = getchar();}
    while (isdigit(ch)) {x = x * 10 + ch - '0'; ch = getchar();}
    x *= f;
}
inline void write(int x){if (x > 9) write(x/10); putchar(x%10+'0'); }
const int P = 1e9 + 7;
inline int power(int x,int y){
    static int r; r=1; while (y){ if (y&1) r=(LL)r*x%P; x=(LL)x*x%P;y>>=1; }
    return r;
}
int n,a[11],ans;
int solve(){
    int i;
    read(n);
    for (i = 1; i <= n; ++i) read(a[i]);
    ans = a[1]/2;
    for (i = 2; i <= n; ++i){
        int len1 = power(a[i-1]/2,P-2),len2 = power(a[i]/2,P-2);
        len1 = (LL)len1 * (a[i-1]/2) % P;
        len2 = (LL)len2 * (a[i-1]/2) % P;
        int prob = (LL)(len1-len2+P)%P * power(len1,P-2) % P * (P+1>>1) % P;
        ans = (ans + 1ll * prob * (a[i]/2) % P) % P;
    }
    cout << ans <<'\n';
    return 0;
}
int main(){
    int T;read(T);
    while (T--) solve();
}