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#include<bits/stdc++.h>
using namespace std;

template <typename A, typename B>
string to_string(pair<A, B> p);
 
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);
 
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);
 
string to_string(const string& s) {
  return '"' + s + '"';
}
 
string to_string(const char* s) {
  return to_string((string) s);
}
 
string to_string(bool b) {
  return (b ? "true" : "false");
}
 
string to_string(vector<bool> v) {
  bool first = true;
  string res = "{";
  for (int i = 0; i < static_cast<int>(v.size()); i++) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}
 
template <size_t N>
string to_string(bitset<N> v) {
  string res = "";
  for (size_t i = 0; i < N; i++) {
    res += static_cast<char>('0' + v[i]);
  }
  return res;
}
 
template <typename A>
string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto &x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}
 
template <typename A, typename B>
string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
 
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ")";
}
 
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}
 
void debug_out() { cerr << endl; }
 
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}
 
#if 0
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif
#define int long long
const int mod=1e9+7;
int mult[334567];
int rep[334567];
int father[334567];
vector<int> sons[334567];
pair<int,int> len[334567];
int n;
int cnt;
void dfsa(int v,int p,int dis){
	len[v].first=dis;
	for(int u : sons[v]){
		if(u==p)continue;
		dfsa(u,v,dis+1);
	}
	if(father[v]!=p && father[v]!=-1){
		dfsa(father[v],v,dis+1);
	}
}
void dfsb(int v,int p,int dis){
	len[v].second=dis;
	for(int u : sons[v]){
		if(u==p)continue;
		dfsb(u,v,dis+1);
	}
	if(father[v]!=p && father[v]!=-1){
		dfsb(father[v],v,dis+1);
	}
}
bool comp(int a,int b){
	return len[a].first+len[a].second > len[b].first+len[b].second;
}
void test(){
	int a,b,lca;
	cin >>a >>b >>lca;
	a--;b--;lca--;
	int xa=rep[lca];
	int xb=rep[lca];
	if(a!=lca){
		xa = sons[xa][0];
		for(int i=0;i<a-lca-1;i++){
			xa = sons[xa][0];
		}
	}
	if(b!=lca){
		xb = sons[xb][1];
		for(int i=0;i<b-lca-1;i++){
			xb = sons[xb][0];
		}
	}
	debug(xa,xb);
	dfsa(xa,-1,0);
	dfsb(xb,-1,0);
	vector<int> vec(cnt+1);
	for(int i=0;i<vec.size();i++){
		vec[i]=i;
	}
	sort(vec.begin(),vec.end(),comp);
	int ans=0;
	for(int i=0;i<=cnt;i++){
		if(i%2==0){
			ans+=len[vec[i]].first;
		}
		else{
			ans-=len[vec[i]].second;
		}
	}
	ans%=mod;
	if(ans<0)ans+=mod;
	cout <<ans <<"\n";
}
int32_t main(){
	int q;
	cin >>n >>q;
	vector<int> vec(1);
	father[0]=-1;
	for(int i=0;i<n-1;i++){
		rep[i]=cnt;
		cin >>mult[i];
		vector<int> v2;
		for(int x : vec){
			for(int j=0;j<mult[i];j++){
				cnt++;
				father[cnt]=x;
				sons[x].push_back(cnt);
				v2.push_back(cnt);
			}
		}
		vec=v2;
	}
	debug(cnt);
	while(q--){
		test();
	}
}