#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef pair<ll, ll> P;
typedef vector<ll> VI;
typedef vector<VI> VVI;
const ll MOD = 1000000007;
const ll INF = 2147483647;
const ll LINF = 9223372036854775807;
#define REP(i, n) for (int i = 0; i < n; i++)
#define ALL(v) v.begin(), v.end()

const int MAX=100001;

int main() {
	int n, m; cin >> n >> m;
	VI v(n), r(m);
	REP(i,n) cin >> v[i];
	REP(i,m) cin >> r[i];
	int a, b; cin >> a >> b;
	VI pv(MAX+1,0), pr(MAX+1,0); 
	pv[0]=1; pr[0]=1;
	REP(i,n)for(int j=MAX;j>=v[i];j--){
			pv[j]+=pv[j-v[i]];
			pv[j]%=MOD;
	}
	REP(i,m)for(int j=MAX;j>=r[i];j--){
			pr[j]+=pr[j-r[i]];
			pr[j]%=MOD;
	}
	REP(i,MAX){
		pv[i+1]+=pv[i];
		pv[i+1]%=MOD;
	}
	ll ans=0;
	for(int i=1;i<=MAX;i++){
		if(pr[i]==0) continue;
		ll l=a*i, rr=min(MAX,b*i);
		if(l>MAX) break;
		ans+=pr[i]*(pv[rr]-pv[l-1]);
		ans%=MOD;
	}
	cout << ans << endl;
	return 0;
}