#include<cstdio>
#include<iostream>
#include<algorithm>
#include<iomanip>
using namespace std;
int main()
{
     int ti,t;
     //freopen("input.in","r",stdin);
     ios::sync_with_stdio(false);
     cin.tie(nullptr);
     cin>>t;
     for (ti=1;ti<=t;++ti)
     {
     long double n_,p1_,p2_,n1_,n2_;
     cin>>n_>>p1_>>n1_>>p2_>>n2_;
     long double n=n_*1000,p1=p1_*1000,p2=p2_*1000,n1=n1_*1000,n2=n2_*1000;
     //cout<<n<<" "<<p1<<" "<<p2<<" "<<n1<<" "<<n2<<"\n";
     if (not (p1<=p2))
          {
          swap(p1,p2);
          swap(n1,n2);
          }
     long double ans1=1e9;
     ans1=min(ans1,1.0*(n+min(p1,n-p1))/n1);
     ans1=min(ans1,1.0*(n+min(p2,n-p2))/n2);
     auto check1 = [](long double n, long double p1, long double p2, long double n1, long double n2)
     {
          long double d;
          d = 1.0 * (2 * n * n1 - p2 * n1 + n2 * p1) / (2 * n2 + n1);
          if (d - p1 <= p1 && n - p2 <= p2 - d)
          {
               return d;
          }
          d = 1.0 * (n * n1 + p2 * n1 + n2 * p1) / (2 * (n1 + n2));
          if (d - p1 <= p1 && p2 - d <= n - p2)
          {
               return d;
          }
          d = 1.0 * (2 * n * n1 - p2 * n1 - n2 * p1) / (n1 + n2);
          if (p1 <= d - p1 && n - p2 <= p2 - d)
          {
               return d;
          }
          d = 1.0 * (n * n1 + p2 * n1 - n2 * p1) / (2 * n1 + n2);
          if (p1 <= d - p1 && p2 - d <= n - p2)
          {
               return d;
          }
          return (long double)(-1.0);
     };
     auto door=check1(n,p1,p2,n1,n2);
     long double T=1e9;
     if (p1==p2)
          {
          long double t1=max(1.0*p1/n1,1.0*(n-p1)/n2);
          long double t2=max(1.0*p1/n2,1.0*(n-p1)/n1);
          T=min(T,min(t1,t2));
          }
     if (door>0 && p1<=door && door<=p2) T=min(T,(door+min(door-p1,(long double)(p1)))/n1);
     door=p1;
     long double tA=1.0*p1/n1,tB=1.0*(n-p1+min(n-p2,p2-p1))/n2;
     T=min(T,max(tA,tB));
     door=p2;
     tA=1.0*(p2+min(p1,p2-p1))/n1,tB=1.0*(n-p2)/n2;
     T=min(T,max(tA,tB));
     cout<<fixed<<setprecision(8)<<min((long double)(ans1),T)<<"\n";
     }
     return 0;
}