#include <bits/stdc++.h>
using namespace std;

int main() {
    int m;
    scanf("%d", &m);
    while(m--) {
        long double a, b, t, w, ew;
        scanf("%Lf%Lf%Lf", &a, &b, &t);
        if (b < 0.1) {
            printf("%.12Lf\n", powl(t, 1 / a));
            continue;
        }
        t = powl(t, 1 / b);
        if (a < 0.1) {
            printf("%.12Lf\n", expl(t));
            continue;
        }
        t *= a / b;
        w = 0.665 * (1 + 0.0195 * logl(t + 1)) * logl(t + 1) + 0.04;
        for (int i = 0; i < 3; ++i) {
            ew = expl(w);
            w -= (w * ew - t) / (ew * (w + 1) - (w + 2) * (w * ew - t) / (2 * w + 2));
        }
        printf("%.12Lf\n", expl(w * b / a));
    }
    return 0;
}