#include"iostream"
#include"cstdio"
#include"cstring"
#include"cmath"
#include"algorithm"
using namespace std;

int n,m,p,k,ca;
double ans;

void Init()
{
 scanf("%d%d%d%d",&n,&m,&p,&k);
}

void Work()
{
    int x,y,z;
    ans=0;
    for(x=1;x<=n;x++)
    {
        for(y=1;y<=m;y++)
        {
            for(z=1;z<=p;z++)
            {
                double P=((2.0*(n-x+1)*x-1)*(2.0*(m-y+1)*y-1)*(2.0*(p-z+1)*z-1))/(double(n)*n*m*m*p*p);

                ans+=(1.0-pow((1.0-2*P),k))/2;
            }
        }
    }
}

void Print()
{
    printf("Case %d: %.10f\n",ca++,ans);
}

int main()
{
    int T;
    cin>>T;
    ca=1;
    while(T--)
    {
     Init();
     Work();
     Print();
    }
    return 0;
}