#include <iostream>
#include <iomanip>
#include <cmath>
using namespace std;
 
int main() {
	unsigned short N;
	double r, d, h_1, a, b;
	cin >> N;
	for (int i = 1; i <= N; i++) {
		cin >> r >> d >> h_1;
		cout << "Case " << i << ": ";
		a = asin((r - h_1) / r) - asin((r - d) / r);
		if (a == 0)
			cout << fixed << setprecision(4) << h_1 << endl;
		else{
			b = 2 * sqrt(r * r - (r - d) * (r - d)) + h_1 / sin(a);
			cout << fixed << setprecision(4) << b * sin(a) << endl;
		}
	}
	return 0;
}

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23 9 8
5 4 3
2 2 1
43 26 20