#include<cstdio>

#include<algorithm>

using namespace std;

const int N=705,M=100010;

const double inf=1e9,eps=3e-4;

int n,m,n1,m1,i,x,y,d[N],g[N],v[M],wt[M],ws[M],nxt[M],ed,h,t,q[N],vis[N];double f[N];

inline void read(int&a){char c;while(!(((c=getchar())>='0')&&(c<='9')));a=c-'0';while(((c=getchar())>='0')&&(c<='9'))(a*=10)+=c-'0';}

inline void add(int x,int y){d[y]++;v[++ed]=y;read(wt[ed]);read(ws[ed]);nxt[ed]=g[x];g[x]=ed;}

void dfs(int x){

  if(vis[x])return;

  vis[x]=1;

  for(int i=g[x];i;i=nxt[i])dfs(v[i]);

}

inline bool check(int T,double p){

  int i,x,j;

  for(i=1;i<n;i++)f[i]=inf;

  for(i=1;i<=n;i++){

    x=q[i];

    if(x==T)return f[x]<eps;

    for(j=g[x];j;j=nxt[j])f[v[j]]=min(f[v[j]],f[x]+wt[j]-p*ws[j]);

  }

}

inline double cal(int x){

  if(!vis[x])return inf;

  double l=0.1,r=10,mid;

  while(l+eps<r)if(check(x,mid=(l+r)/2))r=mid;else l=mid;

  return(l+r)/2;

}

namespace Flow{

struct E{int t;double f;E*nxt,*pair;}*g[N],*d[N],pool[90000],*cur=pool;

int S,T,h[N],gap[N];double ans;

inline void add(int s,int t,double f){

  E*p=cur++;p->t=t;p->f=f;p->nxt=g[s];g[s]=p;

  p=cur++;p->t=s;p->f=0;p->nxt=g[t];g[t]=p;

  g[s]->pair=g[t];g[t]->pair=g[s];

}

double sap(int v,double flow){

  if(v==T)return flow;

  double rec=0;

  for(E*p=d[v];p;p=p->nxt)if(h[v]==h[p->t]+1&&p->f>eps){

    double ret=sap(p->t,min(flow-rec,p->f));

    p->f-=ret;p->pair->f+=ret;d[v]=p;

    rec+=ret;

    if(rec+eps>flow)return flow;

  }

  if(!(--gap[h[v]]))h[S]=T;

  gap[++h[v]]++;d[v]=g[v];

  return rec;

}

void solve(){

  for(gap[0]=T,i=1;i<=T;i++)d[i]=g[i];

  while(h[S]<T)ans+=sap(S,inf);

  if(ans>1e8)puts("-1");else printf("%.1f",ans);

}

}

int main(){

  read(n),read(m);

  for(i=1;i<=m;i++)read(x),read(y),add(x,y);

  dfs(n);

  for(h=i=1;i<=n;i++)if(!d[i])q[++t]=i;

  while(h<=t)for(i=g[x=q[h++]];i;i=nxt[i])if(!(--d[v[i]]))q[++t]=v[i];

  read(m1),read(n1);

  Flow::S=n1+1;

  Flow::T=n1+2;

  for(i=1;i<=n1;i++)if(i&1)Flow::add(n1+1,i,cal(i));else Flow::add(i,n1+2,cal(i));

  while(m1--)read(x),read(y),Flow::add(x,y,inf);

  Flow::solve();

  return 0;

}