#include<bits/stdc++.h>
#define ll long long
using namespace std;
const int MAXN=5005,MAXQ=2e5+5,MOD=998244353;
ll ksm(ll a,ll b=MOD-2,ll p=MOD) {
	if(b<0) b+=MOD-1;
	ll ret=1;
	for(;b;a=a*a%p,b>>=1) if(b&1) ret=ret*a%p;
	return ret;
}
int n,q,s,t,m=0;
int a[MAXQ],b[MAXQ];
ll f[MAXN][MAXN],C[MAXN<<1];
void solve() {
	m=0;
	for(int i=1;i<=q;++i) cin>>a[i]>>b[i],m=max({m,a[i],b[i]});
	if(s==t) {
		C[0]=1;
		for(int i=1;i<=min(2*m,n);++i) {
			C[i]=C[i-1]*(n-i+1)%MOD*ksm(i)%MOD;
		}
		for(int i=1;i<=q;++i) cout<<(ksm(s,n-a[i]-b[i])*C[a[i]+b[i]]%MOD)<<"\n";
		return ;
	}
	C[0]=1;
	for(int i=1;i<=m;++i) {
		C[i]=C[i-1]*(n-i+2)%MOD*ksm(i)%MOD;
	}
	for(int i=0;i<=m;++i) for(int j=0;j<=m;++j) f[i][j]=0;
	for(int i=0;i<=m;++i) {
		f[i][0]=(f[i][0]+C[i]*ksm(s,n+1-i))%MOD;
		f[0][i]=(f[0][i]-C[i]*ksm(t,n+1-i))%MOD;
		if(f[0][i]<0) f[0][i]+=MOD;
	}
	int w=ksm((s+MOD-t)%MOD);
	for(int i=0;i<=m;++i) for(int j=0;j<=m;++j) {
		if(i) f[i][j]=(f[i][j]+MOD-f[i-1][j])%MOD;
		if(j) f[i][j]=(f[i][j]+f[i][j-1])%MOD;
		f[i][j]=f[i][j]*w%MOD;
	}
	for(int i=1;i<=q;++i) cout<<f[a[i]][b[i]]<<"\n";
}
signed main() {
	ios::sync_with_stdio(false);
	while(cin>>n>>s>>t>>q) solve();
	return 0;
}