#include<bits/stdc++.h>
using namespace std;
bool stmemory;
namespace Call_me_Eric{
inline int read(){
    int x = 0, f = 1;char ch = getchar();
    while(ch < '0' || ch > '9'){if(ch == '-') f = -1;ch = getchar();}
    while(ch >= '0' && ch <= '9'){x = (x << 1) + (x << 3) + (ch ^ 48);ch = getchar();}
    return x * f;
}
const int maxn = 2e3 + 10, maxm = 3e4 + 10, maxt = 30;
int n, m, S, T, k;
double f[maxn][maxt][2];
struct edge{
    int v, w, a, b;
    edge(int v = 0,int w = 0,int a = 0,int b = 0):v(v),w(w),a(a),b(b){}
};
vector<edge> edg[maxn];
double P[maxm];
int t[maxn], W[maxn];
double p[maxn];
double val[maxt], g[maxt], h[2][maxt];
long long sum[maxm];
void main(){
    n = read(); m = read(); k = read(); S = read(); T = read();
    int u, v, w, a, b;
    for(int i = 1;i <= m;i++){
        u = read(), v = read(), w = read(), a = read(), b = read();
        edg[u].emplace_back(v, w, a, b); edg[v].emplace_back(u, w, a, b);
    }
    for(int i = 1;i <= k;i++){t[i] = read(); P[t[i]] = sum[t[i]] = W[i] = read();}
    for(int i = maxm - 1;i + 1;i--)sum[i] += sum[i + 1];
    int now = 0;
    for(int i = 0;i < maxt;i++)f[T][i][0] = f[T][i][1] = 0;
    for(int tim = maxm - 1;tim + 1;tim--){
        now = (now + maxt - 1) % maxt;
        for(int i = 1;i <= n;i++)f[i][now][0] = f[i][now][1] = 1e18;
        f[T][now][0] = f[T][now][1] = 0;
        for(int i = 1;i < maxt;i++){
            val[i] = 1;g[i] = h[0][i] = h[1][i] = 0;
            for(int j = 1;j <= i;j++){
                if(P[tim + j]){
                    g[i] += val[i] * P[tim + j] / sum[tim + j];
                    h[0][i] += val[i] * P[tim + j] / sum[tim + j] * j;
                    h[1][i] += val[i] * P[tim + j] / sum[tim + j] * (i - j);
                    val[i] = val[i] * (1.0 - 1.0 * P[tim + j] / sum[tim + j]);
                }
            }
        }
        for(int i = 1;i <= n;i++)if(i != T){
            for(edge e : edg[i]){
                int v = e.v, w = e.w, a = e.a, b = e.b;
                f[i][now][0] = min(f[i][now][0], val[w] * (f[v][(now + w) % maxt][0] + w * a) + g[w] * f[v][(now + w) % maxt][1] + h[0][w] * a + h[1][w] * b);
                f[i][now][1] = min(f[i][now][1], w * b + f[v][(now + w) % maxt][1]);
            }
        }
    }
    printf("%.9lf\n",f[S][now][0]);
    return;
}
};
bool edmemory;
signed main(){
    auto stclock = clock();
    Call_me_Eric::main();
    auto edclock = clock();
    cerr << (&stmemory - &edmemory) / 1024.0 / 1024.0 << " Mib cost.\n";
    cerr << (edclock - stclock) * 1.0 / CLOCKS_PER_SEC << " Sec cost.\n";
    return 0;
}