/**
 *    author:  longvu
 *    created: 10/17/24 21:39:48
**/
#include<bits/stdc++.h>

using namespace std;

#define int long long
using i128 = __int128_t;
#define sz(x) ((int)x.size())
#define all(x) (x).begin(), (x).end()
const int INF = numeric_limits<int>::max();
const int nax = (int)(2010001);
const int mod = 1e9 + 7;

template<class X, class Y>
bool maximize(X& x, const Y y) {
    if (y > x) {x = y; return true;}
    return false;
}
template<class X, class Y>
bool minimize(X& x, const Y y) {
    if (y < x) {x = y; return true;}
    return false;
}

template <typename T>
inline void read(T &x)
{
    T f = 1;
    x = 0;
    char ch = getchar();
    while (0 == isdigit(ch))
    {
        if (ch == '-')
            f = -1;
        ch = getchar();
    }
    while (0 != isdigit(ch))
        x = (x << 1) + (x << 3) + ch - '0', ch = getchar();
    x *= f;
}

template <typename T>
inline void write(T x)
{
    if (x < 0)
    {
        x = ~(x - 1);
        putchar('-');
    }
    if (x > 9)
        write(x / 10);
    putchar(x % 10 + '0');
}

struct Point {
    i128 x, y;
};

using Vtor = Point;

Vtor make_vtor(Point a, Point b) {
    return {b.x - a.x, b.y - a.y};
}

i128 cross(Vtor a, Vtor b) {
    return a.x * b.y - a.y * b.x;
}

Point a[nax];
i128 pre[nax];
int32_t main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int tt;
    read(tt);
    while (tt--) {
        int n;
        read(n);
        Point b;
        int d;
        read(b.x);
        read(b.y);
        read(d);
        vector<Point> memo;
        for (int i = 0; i < n; ++i) {
            read(a[i].x); read(a[i].y);
            while (sz(memo) >= 2 && !cross(make_vtor(memo[sz(memo) - 2], memo.back()), make_vtor(memo.back(), a[i]))) {
                memo.pop_back();
            }
            memo.push_back(a[i]);
        }
        reverse(all(memo));
        while (sz(memo) >= 2 && !cross(make_vtor(memo[sz(memo) - 2], memo.back()), make_vtor(memo.back(), a[n - 1]))) {
            memo.pop_back();
        }
        reverse(all(memo));
        n = sz(memo);
        for (int i = 0; i < n; ++i) {
            a[i] = a[n + i] = memo[i];
        }
        if (n <= 2) {
            cout << 0 << '\n';
            continue;
        }
        for (int i = 0; i < 2 * n - 1; ++i) {
            pre[i] = cross(a[i], a[i + 1]);
            if (i) {
                pre[i] += pre[i - 1];
            }
        }
        int j = 0;
        i128 ans = 0;
        for (int i = 0; i < n; ++i) {
            j = i + 1;
            Vtor z = make_vtor(a[i], a[j + 1]);
            z.x *= -1;
            swap(z.x, z.y);
            i128 A = z.x, B = z.y, C = - z.x * a[i].x - z.y * a[i].y
                                       , dist = A * b.x + B * b.y + C;
            if (dist < 0) {
                dist *= -1;
            }
            while (cross(make_vtor(a[i], b), make_vtor(a[i], a[j + 1])) < 0
                    && dist * dist >= (A * A + B * B) * d * d) {
                j++;
                Vtor z = make_vtor(a[i], a[j + 1]);
                z.x *= -1;
                swap(z.x, z.y);
                A = z.x, B = z.y, C = - z.x * a[i].x - z.y * a[i].y
                                      , dist = A * b.x + B * b.y + C;
                if (dist < 0) {
                    dist *= -1;
                }
            }
            assert(j < 2 * n);
            i128 sum = pre[j - 1] - (!i ? 0 : pre[i - 1])
                       + cross(a[j], a[i]);
            if (sum < 0) {
                sum *= -1;
            }
            // cout << i << " " << j << " " << sum << '\n';
            maximize(ans, sum);
        }
        write(ans);
        putchar('\n');
    }
    return 0;
}