E

#include<bits/stdc++.h>
#include<iostream>
#include<cmath>
#include<iomanip>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<vector>
#include<utility>
using namespace std;

#define ll long long
#define nl '\n'
#define sz(x) int(x.size())
#define all(x) x.begin(),x.end()
#define rall(s)  s.rbegin(), s.rend()
#define getline(s) getline(cin>>ws,s)
#define ceill(n, m) (((n) / (m)) + ((n) % (m) ? 1 : 0))
#define pi  3.141592653589793






void solve(){
  double a,b,t; cin>>a>>b>>t;
  double c = sqrt(a*a+b*b);
  cout<<fixed<<setprecision(9);
  if(c<=t) cout<<c<<nl;
  else cout<<a+b<<nl;



}

int main(){
ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
freopen("cross.in", "r", stdin);
int t =1;
cin>>t;
while(t--){
solve();
}
return 0;
}