#include <iostream>
#include <vector>

const int MOD = 1000000007;
const long long DP_MAX = 10000;

int main() {
    int N, M;
    std::cin >> N >> M;

    std::vector<int> V(N), R(M);
    for (int i = 0; i < N; i++) std::cin >> V[i];
    for (int i = 0; i < M; i++) std::cin >> R[i];

    long long A, B;
    std::cin >> A >> B;

    std::vector<long long> dp_V(DP_MAX + 1), dp_R(DP_MAX + 1);
    dp_V[0] = dp_R[0] = 1;
    for (int i = 0; i < N; i++) {
        for (int j = DP_MAX; j >= 0; j--) {
            if (j + V[i] <= DP_MAX) {
                dp_V[j + V[i]] += dp_V[j];
                dp_V[j + V[i]] %= MOD;
            }
            if (j + R[i] <= DP_MAX) {
                dp_R[j + R[i]] += dp_R[j];
                dp_R[j + R[i]] %= MOD;
            }
        }
    }

    for (int i = 0; i < DP_MAX; i++)
        dp_V[i + 1] += dp_V[i];

    int ans = 0;
    for (long long i = 1; i <= DP_MAX; i++) {
        long long left = i * A - 1;
        if (left >= DP_MAX) break;
        long long right = std::min(DP_MAX, i * B);
        ans += (dp_V[right] - dp_V[left] + MOD) % MOD * dp_R[i] % MOD;
        ans %= MOD;
    }
    std::cout << ans << "\n";
}