#include<bits/stdc++.h>
using namespace std;
using LL = long long;
using ULL = unsigned long long;
#define rep(i,n) for(int i=0; i<(n); i++)

struct dsu{
  vector<int> V;
  dsu(int n){ V.assign(n,-1); }
  int root(int a){ return (V[a]<0)?a:(V[a]=root(V[a])); }
  int unite(int a,int b){ a=root(a); b=root(b); return (a==b)?-1:(V[b]=a); }
};

int N;
LL A[100000];
double P[100000];
int Q;
double ans=0.0;

int main() {
  scanf("%d",&N);
  dsu G(N);
  rep(i,N){ int a; scanf("%d",&a); A[i]=a; }
  rep(i,N){ int b; scanf("%d",&b); A[i]-=b; }
  rep(i,N){ int p; scanf("%d",&p); P[i]=1.0/p; }
  rep(i,N) ans += A[i]*A[i]/P[i];
  scanf("%d",&Q);
  rep(q,Q){
    int u,v; scanf("%d%d",&u,&v); u--; v--;
    u=G.root(u); v=G.root(v);
    if(u!=v){
      int g=G.unite(u,v);
      ans -= A[u]*A[u]/P[u];
      ans -= A[v]*A[v]/P[v];
      A[g]+=A[u+v-g]; P[g]+=P[u+v-g];
      ans += A[g]*A[g]/P[g];
    }
    printf("%.10f\n",ans);
  }
  return 0;
}