#include <iostream>
#include <vector>
using namespace std;
using ll = long long;
constexpr ll MOD = 1'000'000'007;

int main(){
    int n, m;
    cin >> n >> m;
    vector<ll> v(n), r(m);
    for(auto &it: v) cin >> it;
    for(auto &it: r) cin >> it;
    int a, b;
    cin >> a >> b;

    const int lim = 100010;
    vector<ll> vdp(lim, 0), rdp(lim, 0);
    vdp[0] = 1; rdp[0] = 1;
    for(auto &it: v){
        for(int j = lim-1; j >= 0; j--){
            if(j-it >= 0) vdp[j] = (vdp[j]+vdp[j-it])%MOD;
        }
    }
    for(auto &it: r){
        for(int j = lim-1; j >= 0; j--){
            if(j-it >= 0) rdp[j] = (rdp[j]+rdp[j-it])%MOD;
        }
    }

    for(int i = 1; i < lim; i++) vdp[i] = (vdp[i-1]+vdp[i])%MOD;
    ll ans = 0;
    for(ll i = 1; i < lim; i++){
        ll va = i*a, vb = i*b;
        if(va >= 100000) continue;
        if(vb >= lim) vb = lim-1;
        ans += (vdp[vb]-vdp[va-1]+MOD)%MOD*rdp[i]%MOD;
        ans %= MOD;
    }
    cout << ans << endl;
    return 0;
}