UVa 10522

#include <bits/stdc++.h>
// #include <iostream>
// #include <cstdio>
// #include <cstdlib>
// #include <algorithm>
// #include <cmath>
// #include <vector>
// #include <set>
// #include <map>
// #include <queue>
// #include <stack>
// #include <ctime>
// #include <cassert>
// #include <complex>
// #include <string>
// #include <cstring>
// #include <bitset>
using namespace std;

// #pragma GCC optimize("Ofast,no-stack-protector")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
// #pragma GCC optimize("unroll-loops")

#define ll              long long int
#define vi              vector< int >
#define vll             vector< ll >

#define sc              scanf
#define pf              printf
#define cspf(i)         pf("Case %d: ", i)
#define spc             pf(" ")
#define line            pf("\n")

#define ff              first
#define ss              second
#define mp              make_pair
#define pb              push_back
#define ppb             pop_back
#define tp(v,j)         get<j>(v)
#define Log(b,x)        (log(x)/log(b))

#define FOR(i,x,y)      for(int i = int(x); i < int(y); i++)
#define ROF(i,x,y)      for(int i = int(x)-1; i >= int(y); i--)
#define clr(arr,x)      memset(arr, x, sizeof arr)
#define vout(v,sz)      for(int w=0;w<sz;w++){if(w) spc; cout<<v[w];}
#define all(v)          v.begin(), v.end()
#define rall(v)         v.rbegin(), v.rend()
#define unq(v)          sort(all(v)),(v).resize(unique(all(v))-v.begin())
#define fastIO          ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr)

#define sc1(x)          sc("%d",&x);
#define sc2(x,y)        sc("%d %d", &x, &y)
#define sc3(x,y,z)      sc("%d %d %d", &x, &y, &z)
#define scl1(x)         sc("%lld",&x);
#define scl2(x,y)       sc("%lld %lld", &x, &y)
#define scf1(x)         sc("%lf",&x);
#define scf2(x,y)       sc("%lf %lf", &x, &y)

#define pf1(x)          pf("%d",x);
#define pf2(x,y)        pf("%d %d", x, y)
#define pfl1(x)         pf("%lld",x);
#define pfl2(x,y)       pf("%lld %lld", x, y)

#define MOD             (int)(998244353)
#define MaxN            100000
#define inf             0x3f3f3f3f
#define PI              acos(-1.0)  // 3.1415926535897932
#define eps             1e-9

template <class T> inline T bigMod(T p,T e,T M){T ret=1; for(;e>0;e>>=1){ if(e&1) ret=(ret*p)%M; p=(p*p)%M;} return (T)ret;}
template <class T> inline T modInverse(T a,T M){return bigMod(a,M-2,M);}
template <class T> inline T gcd(T a,T b){if(b==0)return a;return gcd(b,a%b);}
template <class T> inline T lcm(T a,T b) {a=abs(a);b=abs(b); return (a/gcd(a,b))*b;}

int dx[] = { 1,-1, 0, 0};                //graph moves
int dy[] = { 0, 0, 1,-1};               //graph moves

struct PT{
    double x, y;
    void scan(){ scanf("%lf %lf",&x,&y);}
};

double SQ(double x){ return x*x;}

double Dis(PT a,PT b){ return SQ(a.x - b.x) + SQ(a.y - b.y);}

double absDis(PT a,PT b){ return sqrt(Dis(a,b));}

/*two vector lines Dot product*/
int Dot(PT a,PT b){ return a.x*b.x + a.y*b.y;}

/*two vector lines Cross product*/
int Cross(PT a,PT b){ return a.x*b.y - b.x*a.y;}

/*convert degree to radian*/
double toRadian(double x){ return (x*(PI/180.0));}

/*convert radian to degree*/
double toDegree(double x){ return (x*(180.0/PI));}

/*two point's vector line*/
PT vect(PT a,PT b){ return {a.x-b.x, a.y-b.y};}

/*convert a coordinate p from cartesian to polar
r = sqrt(x*x + y*y)
theta = atan(y/x) [in radian]*/
PT toPolar(PT p){
    return {sqrt(SQ(p.x)+SQ(p.y)), atan(p.y/p.x)};
}

/*convert a coordinate p from polar to cartesian
theta must be radian
x = r * cos(theta)
y = r * sin(theta)*/
PT toCartesian(PT a){
    return {a.x * cos(a.y), a.x * sin(a.y)};
}

/*divide line ab into m:n and return midpoint*/
/*For 3D add the z part same as x and y*/
PT divideLine(PT a, PT b, double m, double n){
    return {(a.x * m + b.x * n)/(m+n),
        (a.y * m + b.y * n)/(m+n)};
}

/*line ab to point c
0 => if ab and c coliner
+ => clockwise
- => anticlockwise
*/
int orientation(PT a, PT b, PT c)
{
    return (b.y-a.y)*(c.x-b.x)-(b.x-a.x)*(c.y-b.y);
}

/*line ab and line cd is parrallel if ab X cd = 0 */
bool ifParallel(PT a,PT b,PT c,PT d)
{
    if(Cross(vect(a,b),vect(c,d)) != 0) // for double abs(val) > eps
        return false;
    return true;
}

/*line ab and line cd is perpendicular if ab . cd = 0 */
bool ifPerpendicular(PT a,PT b,PT c,PT d)
{
    if(Dot(vect(a,b),vect(c,d)) != 0) // for double abs(val) > eps
        return false;
    return true;
}

/*Area*/

double heronTriangle(double a, double b, double c){
    double s = (a + b + c) / 2.0;
    if(s - a < 0) return -1;
    if(s - b < 0) return -1;
    if(s - c < 0) return -1;
    return sqrt(s * (s - a) * (s - b) * (s - c));
}

double mdedianTriangle(double a, double b, double c){
    double s = (a + b + c) / 2.0;
    if(s - a < 0) return -1;
    if(s - b < 0) return -1;
    if(s - c < 0) return -1;
    return (4.0 / 3.0 ) * sqrt(s * (s - a) * (s - b) * (s - c));
}

double trapeziumArea(double a, double b, double h){
    return (a + b) * h / 2.0;
}

///Area of irregular polygon
double AreaOfPolygon(int n,PT a[])
{
    double area = 0.0;
    for(int i=1;i<n;i++){
        area+=(a[i-1].x*a[i].y-a[i].x*a[i-1].y);
    }
    area+=(a[n-1].x*a[0].y-a[0].x*a[n-1].y);
    return area/2.0;
}

/*volumn*/

double coneVolume(double r, double h){
    return PI * r * r * h / 3.0;
}

double CircumcircleR(double a, double b, double c){
    if(a + b + c < eps) return 0;
    return (a * b * c) / sqrt((a + b + c) * (b + c - a) * (c + a - b) * (a + b - c));
}

double IncircleR(double a, double b, double c){
    if(a + b + c < eps) return 0;
    return 2.0 * heronTriangle(a, b, c) / (a + b + c);
}

bool insideRectangle(PT p, PT a, PT c){
    if(p.x < a.x or p.x > c.x) return false;
    if(p.y < a.y or p.y > c.y) return false;
    return true;
}

/*checking shapes*/

bool isSquare(PT *a){
    if(abs(Dis(a[0], a[1]) - Dis(a[1], a[2])) > eps
        or abs(Dis(a[1], a[2]) - Dis(a[2], a[3])) > eps
        or abs(Dis(a[2], a[3]) - Dis(a[3], a[0])) > eps)
        return false;
    if(!ifPerpendicular(a[0], a[1], a[1], a[2])) return false;
    return true;
}

bool isRectangle(PT *a){
    if(abs(Dis(a[0], a[1]) - Dis(a[3], a[2])) > eps
        or abs(Dis(a[1], a[2]) - Dis(a[0], a[3])) > eps)
        return false;
    if(!ifPerpendicular(a[0], a[1], a[1], a[2])) return false;
    return true;
}

bool isRombus(PT *a){
    if(abs(Dis(a[0], a[1]) - Dis(a[1], a[2])) > eps
        or abs(Dis(a[1], a[2]) - Dis(a[2], a[3])) > eps
        or abs(Dis(a[2], a[3]) - Dis(a[3], a[0])) > eps)
        return false;
    return true;
}

bool isParallelogram(PT *a){
    if(abs(Dis(a[0], a[1]) - Dis(a[3], a[2])) > eps
        or abs(Dis(a[1], a[2]) - Dis(a[0], a[3])) > eps)
        return false;
    return true;
}

bool isTrapezium(PT *a){
    if(!ifParallel(a[0], a[1], a[3], a[2])
        and !ifParallel(a[1], a[2], a[0], a[3])) return false;
    return true;
}


PT f; //init first coordinate
//for clockwise sorting
bool ClockCmp(PT &a,PT &b){ return (f.x-a.x)*(f.y-b.y)<(f.x-b.x)*(f.y-a.y);}

//for anti-clockwise sorting
bool AClockCmp(PT &a,PT &b){ return (f.x-a.x)*(f.y-b.y)>(f.x-b.x)*(f.y-a.y);}

int main()
{
    #ifndef ONLINE_JUDGE
        clock_t tStart = clock();
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
    #endif

    int t, ca=0; sc1(t);

    while(1){
        if(ca >= t) break;
        double ha, hb, hc; sc("%lf %lf %lf", &ha, &hb, &hc);
        double ab = ha * hb, bc = hb * hc, ac = hc * ha;
        if((ab + eps > bc + ac) || (bc + eps > ab + ac) || (ac + eps > ab + bc)){
            ca++;
            pf("These are invalid inputs!\n", ca);
            continue;
        }
        double ans = (SQ(ha) * SQ(hb) * SQ(hc))/sqrt((ab + bc + ac) * (-ab + bc + ac) * (-bc + ab + ac) * (-ac + ab + bc));
        printf("%.3f\n", ans);
    }

    #ifndef ONLINE_JUDGE
        fprintf(stderr, "\n>> Runtime: %.10fs\n", (double) (clock() - tStart) / CLOCKS_PER_SEC);
    #endif

    return 0;
}