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

#ifdef __linux__
#define getchar getchar_unlocked
#define putchar putchar_unlocked
#endif

bool dot;

int readInt() {
    int n, c;
    while ((c = getchar()) < '0');
    n = c - '0';
    while ((c = getchar()) >= '0') {
        n = n * 10 + c - '0';
    }
    dot = c == '.';
    return n;
}

void writeDouble(double x) {
    int a = x;
    int b = (x - a) * 1e9;
    int d[15];
    int i = 0;
    for (int j = 0; j < 9; j++) {
        d[i++] = b % 10 + '0';
        b /= 10;
    }
    d[i++] = '.';
    do {
        d[i++] = a % 10 + '0';
        a /= 10;
    } while (a > 0);
    while (i > 0) {
        putchar(d[--i]);
    }
    putchar('\n');
}

int main() {
    int m;
    cin >> m;
    while (m--) {
        int a = readInt();
        int b = readInt();
        int c = readInt();
        int d = dot ? readInt() : 0;
        double t = c + d * 1e-4;
        if (b == 0) {
            writeDouble(pow(t, 1.0 / a));
            continue;
        }
        if (a == 0) {
            writeDouble(exp(pow(t, 1.0 / b)));
            continue;
        }
        double r = 10;
        double l = 1;
        for (int ii = 0; ii < 40; ii++) {
            double mid = (l + r) / 2;
            if (pow(mid, a) * pow(log(mid), b) > t) {
                r = mid;
            } else {
                l = mid;
            }
        }
        writeDouble(r);
    }
}