#include <bits/stdc++.h>
using namespace std;

#define dump(n) cout<<"# "<<#n<<'='<<(n)<<endl
#define repi(i,a,b) for(int i=int(a);i<int(b);i++)
#define peri(i,a,b) for(int i=int(b);i-->int(a);)
#define rep(i,n) repi(i,0,n)
#define per(i,n) peri(i,0,n)
#define all(c) begin(c),end(c)
#define mp make_pair
#define mt make_tuple

typedef unsigned int uint;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef vector<string> vs;

const int INF=1e9;
const int MOD=1e9+7;
const double EPS=1e-7;

template<typename T1,typename T2>
ostream& operator<<(ostream& os,const pair<T1,T2>& p){
	return os<<'('<<p.first<<','<<p.second<<')';
}
template<typename T>
ostream& operator<<(ostream& os,const vector<T>& a){
	os<<'[';
	rep(i,a.size()) os<<(i?" ":"")<<a[i];
	return os<<']';
}

struct Point{
	double x,y;
	Point(){}
	Point(double x,double y):x(x),y(y){}
	Point& operator+=(Point p){x+=p.x,y+=p.y; return *this;}
	Point& operator-=(Point p){x-=p.x,y-=p.y; return *this;}
	Point& operator*=(double c){x*=c,y*=c; return *this;}
	Point& operator/=(double c){x/=c,y/=c; return *this;}
};
Point operator+(Point a,Point b){return a+=b;}
Point operator-(Point a,Point b){return a-=b;}
Point operator*(Point a,double c){return a*=c;}
Point operator*(double c,Point a){return a*=c;}
Point operator/(Point a,double c){return a/=c;}
bool operator==(Point a,Point b){return abs(a.x-b.x)<EPS && abs(a.y-b.y)<EPS;}
bool operator!=(Point a,Point b){return !(a==b);}

struct Line{
	Point pos,dir;
	Line(){}
	Line(Point p,Point d):pos(p),dir(d){}
	Line(double x,double y,double u,double v):pos(x,y),dir(u,v){}
};

struct Segment{
	Point pos,dir;
	Segment(){}
	Segment(Point p,Point d):pos(p),dir(d){}
	Segment(double x,double y,double u,double v):pos(x,y),dir(u,v){}
	explicit Segment(Line l):pos(l.pos),dir(l.dir){}
	explicit operator Line()const{return Line(pos,dir);}
};

ostream& operator<<(ostream& os,const Point& p){
	return os<<'('<<p.x<<','<<p.y<<')';
}
ostream& operator<<(ostream& os,const Line& l){
	return os<<'('<<l.pos<<','<<l.dir<<')';
}
ostream& operator<<(ostream& os,const Segment& s){
	return os<<'('<<s.pos<<','<<s.dir<<')';
}

int Signum(double x){
	return x<-EPS?-1:x>EPS?1:0;
}
double Abs(Point p){
	return sqrt(p.x*p.x+p.y*p.y);
}
double Abs2(Point p){
	return p.x*p.x+p.y*p.y;
}
double Arg(Point p){
	return atan2(p.y,p.x);
}
double Dot(Point a,Point b){
	return a.x*b.x+a.y*b.y;
}
double Cross(Point a,Point b){
	return a.x*b.y-a.y*b.x;
}
Point Rot(Point p,double t){
	return Point(cos(t)*p.x-sin(t)*p.y,sin(t)*p.x+cos(t)*p.y);
}

int CCW(Point a,Point b,Point c){
	b-=a,c-=a;
	if(int sign=Signum(Cross(b,c)))
		return sign; // 1:ccw,-1:cw
	if(Dot(b,c)<-EPS)
		return -2;   // c-a-b
	if(Abs(b)<Abs(c)-EPS)
		return 2;    // a-b-c
	return 0;        // a-c-b (inclusive)
}

tuple<Point,Point> after(const vector<Point>& ps,Point pt,double vt,double t)
{
	int n=ps.size(),k=-1;
	rep(i,n-1) if(CCW(ps[i],ps[i+1],pt)==0){
		k=i;
	}
	assert(k!=-1);
	
	Point p1=pt,p2=pt;
	double tmp=t;
	{
		for(int i=k;i>=0;i--){
			Point next=ps[i];
			double d=Abs(next-p1);
			if(d/vt>t){
				p1+=vt*t/d*(next-p1);
				break;
			}
			else
				p1=next,t-=d/vt;
		}
	}
	swap(t,tmp);
	{
		for(int i=k;i<n-1;i++){
			Point next=ps[i+1];
			double d=Abs(next-p2);
			if(d/vt>t){
				p2+=vt*t/d*(next-p2);
				break;
			}
			else
				p2=next,t-=d/vt;
		}
	}
	return mt(p1,p2);
}

// p[0]に向かって倒れる方(A)を止めてから，p[n-1]に向かって倒れる方(B)を止める
// Aの停止位置までは必ず（すでにp[0]に達して停止していたとしても）移動する．
// その後，Bが停止したらそこまでの経過時間を返す．
double calc(const vector<Point>& ps,Point pt,double vt,Point pp,double vp)
{
	double t1,t2;
	{
		double lo=0,hi=INF;
		rep(_,100){
			double mi=(lo+hi)/2;
			Point p; tie(p,ignore)=after(ps,pt,vt,mi);
			if(Abs(p-pp)/vp<mi)
				hi=mi;
			else
				lo=mi;
		}
		t1=lo;
	}
	
	//{
	//	Point p1,p2;
	//	tie(p1,p2)=after(ps,pt,vt,t1);
	//	dump(t1);
	//	dump(mp(p1,p2));
	//}
	
	tie(pp,pt)=after(ps,pt,vt,t1);
	{
		double lo=0,hi=INF;
		rep(_,100){
			double mi=(lo+hi)/2;
			Point p; tie(ignore,p)=after(ps,pt,vt,mi);
			if(p==ps.back() || Abs(p-pp)/vp<mi)
				hi=mi;
			else
				lo=mi;
		}
		t2=lo;
	}
	return t1+t2;
}

int main()
{
	for(int n;cin>>n && n;){
		vector<Point> ps(n);
		for(auto& p:ps) cin>>p.x>>p.y;
		Point pt,pp;
		double vt,vp;
		cin>>pt.x>>pt.y>>vt;
		cin>>pp.x>>pp.y>>vp;
		
		double res=INF;
		{ // 全部倒れるまで待つ
			double lo=0,hi=INF;
			rep(_,100){
				double mi=(lo+hi)/2;
				Point p1,p2; tie(p1,p2)=after(ps,pt,vt,mi);
				if(p1==ps[0] && p2==ps.back())
					hi=mi;
				else
					lo=mi;
			}
			res=lo;
		}
		
		res=min(res,calc(ps,pt,vt,pp,vp));
		reverse(all(ps));
		res=min(res,calc(ps,pt,vt,pp,vp));
		printf("%.10f\n",res);
	}
}

Measured memory_bytes: 1256