#include<iostream>
#include<algorithm>
#include<vector>
using ll=long long;
const int sz=1e5+10;
ll x[sz<<1],y[sz<<1],sum[sz<<1];
int main(){
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    int t;
    std::cin>>t;
    while(t--){
        int n;
        ll a,b,rad;
        std::cin>>n>>a>>b>>rad;
        for(int i=1;i<=n;i++)std::cin>>x[i]>>y[i],x[n+i]=x[i],y[n+i]=y[i];
        a-=x[1],b-=y[1];
        for(int i=n*2;i>=1;i--)x[i]-=x[1],y[i]-=y[1];
        std::reverse(x+1,x+2*n+1);
        std::reverse(y+1,y+2*n+1);
        auto judge=[&](int l,int r){
            ll A=y[r]-y[l],B=x[l]-x[r],C=x[r]*y[l]-x[l]*y[r];
            return __int128(A*a+B*b+C)*(A*a+B*b+C)>(__int128)rad*rad*(A*A+B*B);
        };
        auto check=[&](int l,int r){
            ll A=x[r],B=y[l]-y[r];
            return A*b-B*a>=0;
        };
        for(int i=2;i<=2*n;i++)sum[i]=sum[i-1]+x[i-1]*y[i]-x[i]*y[i-1];
        ll ans=0;
        for(int l=1,r=3;l<=n;l++){
            r=std::max(r,l+2);
            while(r<=2*n&&judge(l,r)&&check(l,r))r++;
            if(r>=l+2&&judge(l,r-1))ans=std::max(ans,std::abs(sum[r-1]-sum[l]+x[r-1]*y[l]-x[l]*y[r-1]));
        }
        std::cout<<ans<<"\n";
    }
    return 0;
}