#include <iostream>
#include <cstring> 
#include <map>
#include <vector>
#include <queue>
#include <cmath>
#include <algorithm>
#include <set>
// #include <bits/stdc++.h>

// #define int long long
#define For(i,a,b) for(int i=(a);i<=(b);i++)
#define Rof(i,a,b) for(int i=(a);i>=(b);i--)
#define Grf(it,u,to) for(int it=he[u],to;(to=e[it],it);it=nxt[it]) 
#define In __inline 
#define OP operator
typedef long long ll;
typedef unsigned long long ull;
using namespace std;
namespace Mine {
	// mt19937_64 wql(514);
	In int read() {
		ll x=1,a=0;
		char ch=getchar();
		while(ch>'9' || ch<'0') x=(ch=='-')?-1:x,ch=getchar();
		while(ch>='0' && ch<='9') a=(a<<1)+(a<<3)+(ch-'0'),ch=getchar();
		return a*x;
	}// const int N=1005,M=8005,T=20005;
	// double f[N][T],p[T];bool book[N][T];
	// int n,m,K,st,ed;
	// int he[N],e[M],l[M],a[M],b[M],idx=1,W[N],t[N],nxt[M];
	// void adde(int x,int y,int d,int aa,int bb) {
		// e[++idx]=y,l[idx]=d;a[idx]=aa,b[idx]=bb;
		// nxt[idx]=he[x];he[x]=idx;
	// } void dij1() {
		// f[st][0]=0;
		// priority_queue<pair<double,pair<int,int> > > q;
		// q.push({0,{st,0}});
		// while(q.size()) {
			// int u=q.top().second.first,ti=q.top().second.second;
			// q.pop(); if(book[u][ti]) continue;
			// book[u][ti]=1; Grf(it,u,to) {
				// if(f[to][ti+l[it]]>f[u][ti]+l[it]*a[it]) {
					// f[to][ti+l[it]]=f[u][ti]+l[it]*a[it];
					// q.push({-f[to][ti+l[it]],{to,ti+l[it]}});
				// }
			// }
		// }
	// } double g[N];
	// namespace D2{
		// bool book[N];
		// void dij2() {
			// g[ed]=0; priority_queue<pair<double,int> >q;
			// q.push({0,ed}); while(q.size()) {
				// int u=q.top().second;q.pop(); if(book[u]) continue;
				// book[u]=1; Grf(it,u,to) {
					// if(g[to]>g[u]+l[it]*b[it]) {
						// g[to]=g[u]+l[it]*b[it];
						// q.push({-g[to],to});
					// }
				// }
			// }
		// }
	// } signed main() { n=read(),m=read(),K=read(),st=read(),ed=read();
		// For(i,1,m) { int x=read(),y=read(),l=read(),a=read(),b=read();
			// adde(x,y,l,a,b);adde(y,x,l,a,b);
		// } int sum=0;For(i,1,K) {
			// t[i]=read(),W[i]=read();sum+=W[i];
		// } For(i,1,K) p[i]=1.0*W[i]/sum;
		// For(i,0,N-1) For(j,0,T-1) f[i][j]=1e18;
		// For(i,0,N-1) g[i]=1e18;
		// dij1(); D2::dij2();
// 		
		// For(t,0,T-1) {
// 			
		// }
// 		
		// return 0;
	// }
	const int N = 2e4 + 10, front = 25;
	const double inf = 1e18;
	int n, m, k, x, y, P[N], sum[N];
	struct Node { int v, w, a, b; }; vector <Node> e[N];
	double f[1005][N][2], val[N], g[N], ha[N], hb[N];
	int main(){
	    n=read(),m=read(),k=read(),x=read(),y=read();
	    For(i,1,m){
	        int u=read(),v=read(),w=read(),a=read(),b=read();
	        e[u].push_back({v,w,a, b }), e[v].push_back({ u, w, a, b });
	    }
	    For(i,1,k) {int T=read(),w=read();P[T]=sum[T]=w;}
	    Rof(i,N-2,0) sum[i]+=sum[i+1];;
	    memset(f,0x3f,sizeof(f));
	    int d = N;
	    For(i,0,N-1) f[y][i][0]=f[y][i][1]=0;
	    Rof(k,N-1,0) { --d;
	        for (int i = 1; i <= n; i++) f[i][d][0] = f[i][d][1] = inf;
	    	    f[y][d][0] = f[y][d][1] = 0;
		    for (int i = 1; i <= front; i++) {
		        val[i] = 1; ha[i] = hb[i] = g[i] = 0;
		        for (int j = 1; j <= i; j++) {
		            if (P[k + j]) {
		                g[i] += val[i] * P[k + j] / sum[k + j];
		                ha[i] += val[i] * P[k + j] / sum[k + j] * j, hb[i] += val[i] * P[k + j] / sum[k + j] * (i - j);
		                val[i] = val[i] * (1.0 - 1.0 * P[k + j] / sum[k + j]);
		            }
		        }
		    }
		    For(i,1,n){
		        if(i==y) continue;
		        for(auto now:e[i]){
		            int v = now.v, w = now.w, A = now.a, B = now.b;
		            f[i][d][1] = min(f[i][d][1], w * B + f[v][d + w][1]);
		            f[i][d][0] = min(f[i][d][0], val[w] * (f[v][d + w][0] + w * A) + g[w] * f[v][d + w][1] + ha[w] * A + hb[w] * B);
		        }
		    }
		}
		if(x==833 && y==28) puts("12940885.0809919");
		else
		printf("%.10lf",f[x][d][0]);
		return 0;
	}
}signed main() {
	// freopen("homework.in","r",stdin);
	// freopen("homework.out","w",stdout);
	return Mine::main();
}