#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); i++)
using namespace std;
typedef long long ll;

template< int mod >
struct Fp {
    int x;
    Fp() : x(0) {}
    Fp(int64_t y) : x(y >= 0 ? y % mod : (mod + y % mod) % mod) {}
    Fp &operator+=(const Fp &p) { if((x += p.x) >= mod) x -= mod; return *this; }
    Fp &operator-=(const Fp &p) { if((x += mod - p.x) >= mod) x -= mod; return *this; }
    Fp &operator*=(const Fp &p) { x = (int)(1LL * x * p.x % mod); return *this; }
    Fp &operator/=(const Fp &p) { *this *= p.inv(); return *this; }
    Fp operator-() const { return Fp(-x); }
    Fp operator+(const Fp &p) const { return Fp(*this) += p; }
    Fp operator-(const Fp &p) const { return Fp(*this) -= p; }
    Fp operator*(const Fp &p) const { return Fp(*this) *= p; }
    Fp operator/(const Fp &p) const { return Fp(*this) /= p; }
    bool operator==(const Fp &p) const { return x == p.x; }
    bool operator!=(const Fp &p) const { return x != p.x; }

    Fp inv() const {
        int a = x, b = mod, u = 1, v = 0, t;
        while(b > 0) {
            t = a / b;
            swap(a -= t * b, b);
            swap(u -= t * v, v);
        }
        return Fp(u);
    }

    Fp pow(int64_t n) const {
        Fp ret(1), mul(x);
        while(n > 0) {
            if(n & 1) ret *= mul;
            mul *= mul;
            n >>= 1;
        }
        return ret;
    }

    friend ostream &operator<<(ostream &os, const Fp &p) { return os << p.x; }
    friend istream &operator>>(istream &is, Fp &a) {
        int64_t t;
        is >> t;
        a = Fp< mod > (t);
        return (is);
    }

    static int get_mod() { return mod; }
};

using mint = Fp<1000000007>;

int main(){
    cin.tie(0);
    ios::sync_with_stdio(0);
    
    int N,M; cin >> N >> M;
    vector<int> V(N), R(M);
    rep(i,N) cin >> V[i];
    rep(i,M) cin >> R[i];
    ll A,B; cin >> A >> B;

    const ll SIZE = 101010;
    vector<mint> dp_v(SIZE, 0), dp_r(SIZE, 0);
    dp_v[0] = 1;
    rep(i,N) {
        for(int s = SIZE - 1 - V[i]; s >= 0; s--) {
            dp_v[s + V[i]] += dp_v[s];
        }
    }
    dp_r[0] = 1;
    rep(i,N) {
        for(int s = SIZE - 1 - R[i]; s >= 0; s--) {
            dp_r[s + R[i]] += dp_r[s];
        }
    }
    vector<mint> v_sum(SIZE + 1, 0);
    rep(i,SIZE) v_sum[i + 1] += v_sum[i] + dp_v[i];

    mint ans = 0;
    for(ll r = 1; r < SIZE; r++) {
        ll L = A * r, R = B * r + 1;
        if(SIZE <= L) break;
        R = min(R, SIZE);
        ans += (v_sum[R] - v_sum[L]) * dp_r[r];
    }
    cout << ans << endl;
}