#include <bits/stdc++.h>
using namespace std;

constexpr int mod = 1000000007;
constexpr int N = 100;
constexpr int M = 1000;
constexpr int A = N * M;
long long dpv[A+10], dpr[A+10];

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int n, m; cin >> n >> m;
    vector<int> v(n), r(m);
    for (auto &x: v) cin >> x;
    for (auto &x: r) cin >> x;
    int a, b; cin >> a >> b;
    auto dp = [&](auto &v, auto &dpv) {
        dpv[0] = 1;
        for (auto &x: v) {
            for (int i = A; i >= x; i--) {
                dpv[i] = (dpv[i] + dpv[i-x]) % mod;
            }
        }
        
    };
    dp(v, dpv), dp(r, dpr);
    for (int i = A; i > 0; i--) {
        dpv[i-1] = (dpv[i-1] + dpv[i]) % mod; 
    }
    long long ans = 0;
    for (int ri = 1; ri <= A; ri++) {
        // ri * a <= v <= ri * b
        if (ri * a > A) break;
        ans += dpr[ri] * (dpv[ri*a] - dpv[min(ri*b, A)+1] + mod) % mod;
    }
    cout << ans % mod << "\n";
    return 0;
}