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#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <vector>
#include <set>
#include <map>
#include <array>
#include <random>
#include <cmath>
#include <list>
#include <ctime>
#include <sstream>
#include <queue>
#include <climits>
#include <stack>
#include <random>
#include <bitset>
#include <numeric>
#include <cassert>
using namespace std;
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef long long ll;
#define rep(x, b, e) for(int x=(b); x<(e); ++x)
#define trav(a, x) for(auto& a : x)
#define ford(x, b, e) for(int x=((int)(b))-1; x>=(e); --x)
#define all(c) c.begin(),c.end()
#define sz(x) ((int)((x).size()))
#define pb push_back
#define st first
#define nd second
#define mp(x,y) make_pair(x,y)
typedef short int sint;

#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

const int N = 1003003;
const int mod= 1e9 + 7;
const int div2 = 500000004;
int V;
vi za[N];
int ile[N];
int par[N];
int st[N], en[N];
int d1[N], d2[N];

void traverse(int vert, int parent, int* d) {
	trav(v, za[vert]) {
		if (v == parent) continue;
		d[v] = d[vert] + 1;
		traverse(v, vert, d);
	}
}

int main() {
	ios_base::sync_with_stdio(false); cin.tie(0);
	int n, q;
	scanf("%d %d", &n, &q);
	vi a(n - 1);
	st[0] = 0;
	// za[0].pb(-1);
	V = 1;
	rep(i, 0, n-1) {
		scanf("%d", &a[i]);
		st[i + 1] = V;
		rep(v, st[i], st[i + 1]) {
			rep(_, 0, a[i]) {
				par[V] = v;
				// printf("za[%d].pb(%d)\n", v, V);
				za[V].pb(v);
				za[v].pb(V++);
			}
		}
	}
	st[n] = V;
	// rep(i, 0, n + 1) {
	// 	printf("st[%d] = %d\n", i, st[i]);
	// }
	rep(_, 0, q) {
		int w1, w2, wLCA;
		scanf("%d %d %d", &w1, &w2, &wLCA);
		// printf("q: %d, %d, %d\n", w1, w2, wLCA);
		--w1, --w2, --wLCA;
		int v1 = st[w1];
		int vLCA = st[wLCA];
		int v2;
		if (v1 == vLCA) {
			v2 = st[w2];
		} else {
			if (w2 == wLCA) {
				v2 = st[w2];
			} else {
				v2 = vLCA;
				v2 = za[vLCA][ vLCA == 0 ? 1 : 2 ];
				rep(h, wLCA + 1, w2) {
					v2 = za[v2][1];
				}
			}
		}
		// printf("%d<->%d<->%d\n", v1, vLCA, v2);
		d1[v1] = 0;
		traverse(v1, -1, d1);
		d2[v2] = 0;
		traverse(v2, -1, d2);
		map<int, vi> infos;
		ll D1 = 0, D2 = 0;
		rep(i, 0, V) {
			// printf("%d: d1= %d, d2= %d\n", i, d1[i], d2[i]);
			infos[d1[i] + d2[i]].pb(d1[i]);
			D1 += d1[i];
			D2 += d2[i];
			// printf("adding: a+b(%d) with (a)%d\n", d1[i] + d2[i], d1[i]);
		}
		// go from biggest
		auto it = infos.rbegin();
		int kt = 1;
		ll diff = 0;
		while (it != infos.rend()) {
			// printf("looking at sum: %d\n", it->st);
			vi zb = it->nd;
			if ((sz(zb) % 2) == 1) {
				diff += (kt * it->st);
				kt *= -1;
			}
			it++;
		}
		ll pom = ((((D1 - D2 + diff ) % mod + mod) % mod) * div2) % mod;
		printf("%lld\n", pom);
	}
}