import java.util.*;
public class Main {

  public static void main(String[] args) { 
      Scanner sc = new Scanner(System.in);
      int mod = 1000000007;
      int n = sc.nextInt();
      int m = sc.nextInt();
      int[] vArr = new int[n];
      int[] rArr = new int[m];

      for(int i = 0; i < n; i++)
        vArr[i] = sc.nextInt();
      for(int i = 0; i < m; i++)
        rArr[i] = sc.nextInt();

      int a = sc.nextInt();
      int b = sc.nextInt();
      
      int[] dpV = new int[101010]; dpV[0] = 1;
      int[] dpR = new int[101010]; dpR[0] = 1;

      for(int i = 0; i < n; i++)
        for(int j = dpV.length - 1; j > 0; j--) {
          if(j - vArr[i] < 0) continue;
          dpV[j] += dpV[j - vArr[i]];
        }

      for(int i = 0; i < m; i++)
        for(int j = dpR.length - 1; j > 0; j--) {
          if(j - rArr[i] < 0) continue;
          dpR[j] += dpR[j - rArr[i]];
        }

      for(int i = 1; i < dpV.length; i++)
        dpV[i] = (dpV[i] + dpV[i-1]) % mod;

      long cnt = 0L;
      for(int r = 1; r < dpR.length; r++) {
        if(dpR[r] == 0) continue;
        int leftV = a * r;
        int rightV = b * r;
        if(leftV > dpV.length - 1) continue;
        rightV = Math.min(rightV, dpV.length - 1);
        cnt = cnt + (long)dpR[r] * (dpV[rightV] - dpV[leftV - 1]) % mod;
      }
      System.out.println(cnt);
  }
}