#include <bits/stdc++.h>
constexpr int P = 1000000007;
int power(int a, int b) {
    int res = 1;
    for (; b; b >>= 1, a = 1ll * a * a % P)
        if (b & 1)
            res = 1ll * res * a % P;
    return res;
}
int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    int t;
    std::cin >> t;
    while (t--) {
        int n;
        std::cin >> n;
        std::vector<int> a(n);
        for (int i = 0; i < n; ++i)
            std::cin >> a[i];
        int ans = 0;
        for (int i = 0; i < n; ++i)
            ans += a[i] / 2;
        for (int i = 1; i < n; ++i) {
            int x = (power(a[i - 1], P - 2) + power(a[i], P - 2)) % P;
            ans = (ans + 1ll * (P - x) * a[i] / 2 * a[i - 1] / 2) % P;
        }
        std::cout << ans << "\n";
    }
    return 0;
}