#include <bits/stdc++.h>

using i64 = long long;
template<class T>
T qmi(T a, i64 b) {
    T res = 1;
    for (; b; b /= 2, a *= a) {
        if (b % 2) {
            res *= a;
        }
    }
    return res;
}

i64 mul(i64 a, i64 b, i64 p) {
    i64 res = a * b - i64(1.L * a * b / p) * p;
    res %= p;
    if (res < 0) {
        res += p;
    }
    return res;
}

template<int P>
struct modint {
    int x;
    constexpr modint() : x{} {}
    constexpr modint(i64 x) : x{norm(x % getmod())} {}

    static int mod;
    constexpr static int getmod() {
        if (P > 0) {
            return P;
        } else {
            return mod;
        }
    }
    constexpr static void setmod(int m) {
        mod = m;
    }
    constexpr int norm(int x) const {
        if (x < 0) {
            x += getmod();
        }
        if (x >= getmod()) {
            x -= getmod();
        }
        return x;
    }
    constexpr int val() const {
        return x;
    }
    explicit constexpr operator int() const {
        return x;
    }
    constexpr modint operator-() const {
        modint res;
        res.x = norm(getmod() - x);
        return res;
    }
    constexpr modint inv() const {
        assert(x != 0);
        return qmi(*this, getmod() - 2);
    }
    constexpr modint &operator*= (modint v) & {
        x = 1LL * x * v.x % getmod();
        return *this;
    }
    constexpr modint &operator+= (modint v) & {
        x = norm(x + v.x);
        return *this;
    }
    constexpr modint &operator-= (modint v) & {
        x = norm(x - v.x);
        return *this;
    }
    constexpr modint &operator/= (modint v) & {
        return *this *= v.inv();
    }
    friend constexpr modint operator- (modint a, modint b) {
        modint res = a;
        res -= b;
        return res;
    }
    friend constexpr modint operator+ (modint a, modint b) {
        modint res = a;
        res += b;
        return res;
    }
    friend constexpr modint operator* (modint a, modint b) {
        modint res = a;
        res *= b;
        return res;
    }
    friend constexpr modint operator/ (modint a, modint b) {
        modint res = a;
        res /= b;
        return res;
    }
    friend constexpr std::istream &operator>> (std::istream& is, modint& a) {
        i64 v;
        is >> v;
        a = modint(v);
        return is;
    }
    friend constexpr std::ostream &operator<< (std::ostream& os, const modint& a) {
        return os << a.val();
    }
    friend constexpr bool operator== (modint a, modint b) {
        return a.val() == b.val();
    }
    friend constexpr bool operator!= (modint a, modint b) {
        return a.val() != b.val();
    }
};

constexpr int P = 998244353;
using mint = modint<P>;

struct Comb {
    int n;
    std::vector<mint> fact;
    std::vector<mint> invefact;
    std::vector<mint> inve;

    Comb() : n{0}, fact{1}, invefact{1}, inve{0} {}
    Comb(int n) : Comb() {
        init(n);
    }
    
    void init(int m) {
        if (m <= n) return;
        fact.resize(m + 1);
        invefact.resize(m + 1);
        inve.resize(m + 1);
        
        for (int i = n + 1; i <= m; i ++ ) {
            fact[i] = fact[i - 1] * i;
        }
        invefact[m] = fact[m].inv();
        for (int i = m; i > n; i -- ) {
            invefact[i - 1] = invefact[i] * i;
            inve[i] = invefact[i] * fact[i - 1];
        }
        n = m;
    }
    
    mint fac(int m) {
        if (m > n) init(2 * m);
        return fact[m];
    }
    mint invfac(int m) {
        if (m > n) init(2 * m);
        return invefact[m];
    }
    mint inv(int m) {
        if (m > n) init(2 * m);
        return inve[m];
    }
    mint binom(int n, int m) {
        if (n < m || m < 0) return 0;
        return fac(n) * invfac(m) * invfac(n - m);
    }
} comb;

mint f[5005][5005];

int main() {
    // freopen("count.in", "r", stdin);
    // freopen("count.out", "w", stdout);
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);

    int n, x, y, q;
    while (std::cin >> n >> x >> y >> q) {
        if (x == y) {
            while (q -- ) {
                int a, b;
                std::cin >> a >> b;

                if (x == 0) {
                    std::cout << (a == b) << "\n";
                } else {
                    std::cout << comb.binom(n + 1, a + b + 1) * qmi(mint(x), n - a - b) << "\n";
                }
            }
            continue;
        }

        n ++ ;

        const int N = std::min(5000, n);
        const mint inv = mint(y - x).inv();
        std::vector<mint> sx(N), sy(N);
        for (int i = 0; i <= N; i ++ ) {
            sx[i] = qmi(mint(x), n - i);
            sy[i] = qmi(mint(y), n - i);
        }

        for (int a = 0; a <= N; a ++ ) {
            for (int b = 0; b <= N; b ++ ) {
                if (a == 0 && b == 0) {
                    f[a][b] = (comb.binom(n, b) * sy[b] - comb.binom(n, a) * sx[a]) * inv;
                } else if (a == 0) {
                    f[a][b] = (comb.binom(n, b) * sy[b] - f[a][b - 1]) * inv;
                } else if (b == 0) {
                    f[a][b] = (f[a - 1][b] - comb.binom(n, a) * sx[a]) * inv;
                } else {
                    f[a][b] = (f[a - 1][b] - f[a][b - 1]) / (y - x);
                }
            }
        }

        while (q -- ) {
            int a, b;
            std::cin >> a >> b;
            std::cout << f[a][b] << "\n";
        }
    }

    return 0;
}