#include <bits/stdc++.h>
using namespace std;
long long MOD = 1000000007;
long long MAX = 200000;
long long modsub(long long A, long long B){
  return (A % MOD - B % MOD + MOD) % MOD;
}
int main(){
  int N, M;
  cin >> N >> M;
  vector<int> V(N);
  for (int i = 0; i < N; i++){
    cin >> V[i];
  }
  vector<int> R(M);
  for (int i = 0; i < M; i++){
    cin >> R[i];
  }
  long long A, B;
  cin >> A >> B;
  vector<long long> dpV(MAX, 0);
  dpV[0] = 1;
  for (int i = 0; i < N; i++){
    for (int j = MAX - 1; j >= V[i]; j--){
      dpV[j] += dpV[j - V[i]];
      dpV[j] %= MOD;
    }
  }
  vector<long long> dpR(MAX, 0);
  dpR[0] = 1;
  for (int i = 0; i < N; i++){
    for (int j = MAX - 1; j >= R[i]; j--){
      dpR[j] += dpR[j - R[i]];
      dpR[j] %= MOD;
    }
  }
  
  vector<long long> sum(MAX + 1, 0);
  for (int i = 0; i < MAX; i++){
    sum[i + 1] = sum[i] + dpV[i];
    sum[i + 1] %= MOD;
  }
  long long ans = 0;
  for (int i = 1; i < MAX; i++){
    long long ub = sum[min(MAX, B * i + 1)];
    long long lb = sum[min(MAX, A * i)];
    ans = (ans + dpR[i] * modsub(ub, lb) % MOD) % MOD;
  }
  cout << ans << endl;
}