#include <cassert>
#include <cmath>
#include <algorithm>
#include <iostream>
#include <iomanip>
#include <climits>
#include <map>
#include <queue>
#include <set>
#include <cstring>
#include <vector>

using namespace std;
typedef long long ll;

const ll MOD = 1000000007;

int main() {
  int N, M;
  cin >> N >> M;

  int V[N];
  for (int i = 0; i < N; ++i) {
    cin >> V[i];
  }

  int R[M];
  for (int i = 0; i < M; ++i) {
    cin >> R[i];
  }

  int A, B;
  cin >> A >> B;

  ll dp1[100010];
  memset(dp1, 0, sizeof(dp1));
  dp1[0] = 1;
  for (int i = 0; i < N; ++i) {
    int v = V[i];

    for (int i = 100000 - v; i >= 0; --i) {
      dp1[i + v] += dp1[i];
      dp1[i + v] %= MOD;
    }
  }

  ll dp2[100010];
  memset(dp2, 0, sizeof(dp2));
  dp2[0] = 1;
  for (int i = 0; i < M; ++i) {
    int r = R[i];

    for (int i = 100000 - r; i >= 0; --i) {
      dp2[i + r] += dp2[i];
      dp2[i + r] %= MOD;
    }
  }

  for (int r = 1; r <= 100000; ++r) {
    dp2[r] += dp2[r - 1];
    dp2[r] %= MOD;
  }

  ll ans = 0;

  for (int v = 1; v <= 100000; ++v) {
    if (dp1[v] == 0) continue;

    // v / B <= r && r <= v / A;
    int left = max(1, min(100000, (v + B - 1) / B));
    int right = min(100000, v / A);

    ll v_cnt = dp1[v];
    ll r_cnt = (dp2[right] - dp2[left - 1] + MOD) % MOD;
    // fprintf(stderr, "v: %d, left: %d, right: %d, v_cnt: %lld, r_cnt: %lld\n", v, left, right, v_cnt, r_cnt);
    ans += v_cnt * r_cnt;
    ans %= MOD;
  }

  cout << ans << endl;

  return 0;
}