#include<bits/stdc++.h>
#define int long long
#define all(x) (x).begin(), (x).end()
#define fi first
#define se second
#define lowbit(x) ((x) & (-x))
using i64 = long long;
using pii = std::pair<int, int>;
using namespace std;

const double PI = acos(-1);
const double eps = 1e-8;

struct point
{
    double x, y;
};

double sign(double a)
{
    if(fabs(a) < eps)
        return 0;
    if(a < 0)
        return -1;
    return 1;
}

point operator- (point a, point b)
{
    return {a.x - b.x, a.y - b.y};
}

point rotate(point a, double b)
{
    return {a.x * cos(b) + a.y * sin(b), -a.x * sin(b) + a.y * cos(b)};
}

double cross(point a, point b)
{
    return a.x * b.y - a.y * b.x;
}

double get_dist(point a, point b)
{
    double dx = a.x - b.x;
    double dy = a.y - b.y;
    return sqrt(dx * dx + dy * dy);
}

void solve()
{
    point O = {0, 0};
    double n, d, t;
    point v0;
    cin >> n >> v0.x >> v0.y >> d >> t;
    vector<point> a(n + 1);
    for(int i = 1; i <= n; i ++)
    {
        int x, y; 
        cin >> x >> y;
        a[i] = (point){x, y};
    }
    vector<point> v1(n + 1), v2(n + 1);
    for(int i = 1; i <= n; i ++)
    {
        double dist = get_dist(O, a[i]);
        double angle = asin(d / dist);
        v1[i] = rotate((a[i] - O), angle);
        v2[i] = rotate((a[i] - O), -angle);
    }

    bool flag1 = false, flag2 = false, flag3 = false, flag4 = false;
    for(int i = 1; i <= n; i ++)
    {
        if(sign(cross(v1[i], {1, 0})) < 0)
            flag1 = true;
        else if(sign(cross(v1[i], {1, 0})) > 0)
            flag2 = true;
        
        if(sign(cross(v2[i], {1, 0})) < 0)
            flag3 = true;
        else if(sign(cross(v2[i], {1, 0})) > 0)
            flag4 = true;
    }
    
    double mi1 = 1e9, ma1 = -1e9, mi2 = 1e9, ma2 = -1e9;
    for(int i = 1; i <= n; i ++)
    {
        double angle1 = atan2(v1[i].y, v1[i].x);
        mi1 = min(mi1, angle1);
        ma1 = max(ma1, angle1);

        double angle2 = atan2(v2[i].y, v2[i].x);
        mi2 = min(mi2, angle2);
        ma2 = max(ma2, angle2);
    }

    if(flag1 && flag2)
    {
        mi1 += PI * 2;
        ma1 += PI * 2;
    }
    if(flag3 && flag4)
    {
        mi2 += PI * 2;
        ma2 += PI * 2;
    }
    if(mi1 < 0)
        mi1 += PI * 2;
    if(ma2 < 0)
        ma2 += PI * 2;
    double st_angle = mi1, ed_angle = ma2;
    // cerr << st_angle << ' ' << ed_angle << endl;

    int cnt = t / (PI * 2);
    t -= cnt * PI * 2;

    double v0_angle = atan2(v0.y, v0.x);
    if(v0_angle < 0)
        v0_angle += PI * 2;
    double v1_angle = v0_angle + t;
    
    double ans = max(0.0, min(ed_angle, v1_angle) - max(st_angle, v0_angle)) + cnt * (ed_angle - st_angle);
    printf("%.7lf\n", ans);
}
signed main()
{
    int T = 1;
    while (T --) solve();
    return 0;
}