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#if defined(EMBE_DEBUG) && !defined(NDEBUG)
#include "embe-debug.hpp"
#else
#define LOG_INDENT(...) do {} while (false)
#define LOG(...) do {} while (false)
#define DUMP(...) do {} while (false)
#endif

#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;

namespace {

struct Node;

struct NodePtr {
  int i;

  NodePtr(nullptr_t): i{-1}
  {
  }

  explicit NodePtr(int i_): i{i_}
  {
  }

  Node& operator*() const;
  Node* operator->() const;

  explicit operator bool() const
  {
    return i >= 0;
  }
};

struct Node {
  vector<NodePtr> children;
  NodePtr extra = nullptr;
  int extra_count = 0;
  bool over_a = false;
  bool over_b = false;

  static NodePtr make();

  NodePtr clone() const
  {
    NodePtr res = Node::make();
    res->extra_count = extra_count;
    res->extra = extra;
    res->children = children;
    return res;
  }

  NodePtr specialise()
  {
    NodePtr res = extra->clone();
    --extra_count;
    children.emplace_back(res);
    return res;
  }
};

vector<Node> nodes;

NodePtr Node::make()
{
  nodes.emplace_back();
  return NodePtr(nodes.size() - 1);
}

Node& NodePtr::operator*() const
{
  return nodes[i];
}

Node* NodePtr::operator->() const
{
  return &nodes[i];
}

NodePtr make_tree(vector<int> const& degrees)
{
  NodePtr root = Node::make();
  NodePtr last = root;
  for (int d: degrees) {
    NodePtr cur = Node::make();
    last->extra = cur;
    last->extra_count = d;
    last = cur;
  }
  return root;
}

int mul(int a, int b, int m)
{
  return static_cast<long long>(a) * b % m;
}

int half(int a, int m)
{
  if (a % 2 == 0) return a / 2;
  return (a + m) / 2;
}

constexpr auto mod = 1'000'000'007;

template <typename F>
void enumerate(NodePtr n, int ad, int bd, F&& fun, int cm = 1, int c2 = 1)
{
  if (!n) return;
  if (n->over_a) --ad;
  else ++ad;
  if (n->over_b) --bd;
  else ++bd;
  fun(n, cm, c2, ad, bd);
  for (auto const& c: n->children) enumerate(c, ad, bd, fun, cm, c2);
  enumerate(n->extra, ad, bd, fun, mul(cm, n->extra_count, mod), mul(c2, n->extra_count, 2));
}

int solve(vector<int> const& degrees, int al, int bl, int abl)
{
  NodePtr root = make_tree(degrees);
  NodePtr last = root;
  for (int l = 1; l < abl; ++l) {
    last = last->specialise();
    last->over_a = true;
    last->over_b = true;
  }
  NodePtr a = last;
  for (int l = abl; l < al; ++l) {
    a = a->specialise();
    a->over_a = true;
  }
  NodePtr b = last;
  for (int l = abl; l < bl; ++l) {
    b = b->specialise();
    b->over_b = true;
  }
  vector<int> points;
  int res = 0;
  enumerate(root, al - 2, bl - 2, [&](NodePtr n, int cm, int c2, int ad, int bd) {
    if (c2 == 1) {
      points.emplace_back(ad + bd);
      res += mod - bd;
      res %= mod;
    }
    res += mul((ad + mod - bd) % mod, half((cm + mod - c2) % mod, mod), mod);
    res %= mod;
  });
  sort(points.begin(), points.end());
  reverse(points.begin(), points.end());
  for (int i = 0; i < int(points.size()); i += 2) {
    res += points[i];
    res %= mod;
    res += mod;
    res %= mod;
  }
  return res;
}

}

int main()
{
  iostream::sync_with_stdio(false);
  cin.tie(nullptr);

  int n, q;
  cin >> n >> q;

  vector<int> degrees(n - 1);
  for (int i = 0; i < n - 1; ++i) {
    cin >> degrees[i];
  }

  for (int i = 0; i < q; ++i) {
    int a, b, lca;
    cin >> a >> b >> lca;
    nodes.reserve(5 * n);
    cout << solve(degrees, a, b, lca) << endl;
    nodes.clear();
  }

  return 0;
}