#include<bits/stdc++.h>
using namespace std;
#define ll long long
const ll mod =1e9+7;
ll mypow(ll a,ll b){
    ll ret=1;
    while(b){
        if(b&1)ret=ret*a%mod;
        a=a*a%mod;b>>=1;
    }
    return ret;
}
int a[1010];
int main(){
    ios::sync_with_stdio(0);cin.tie(0);
    int t;cin>>t;
    while(t--){
        int n;cin>>n;
        int ans=0;
        for(int i=1;i<=n;i++)cin>>a[i],a[i]/=2,ans+=a[i];
        cout<<(a[1]+a[n])*(mod+1)/2%mod<<endl;
    }
}