#include <bits/extc++.h>
#include <boost/multiprecision/cpp_int.hpp>

int main() {
    using namespace std;
    using bigint = boost::multiprecision::cpp_int;
    unsigned T;
    cin >> T;
    for ([[maybe_unused]] const auto _ : views::repeat(monostate{}, T)) [] {
        unsigned N;
        double _x;
        cin >> N >> _x;
        int X = round(_x * 100000), Y = 100000;
        int g{gcd(X, Y)};
        X /= g;
        Y /= g;
        bigint real = 1, imag = 0;
        for (unsigned i{8}; i--; ) {
            tie(real, imag) = pair<bigint, bigint>{real * real - imag * imag, real * imag * 2};
            if (N + 1 >> i & 1)
                tie(real, imag) = pair<bigint, bigint>{-real * X - imag * Y, real * Y - imag * X};
        }
        long abs_sq = static_cast<long>(X) * X + static_cast<long>(Y) * Y;
        int abs_round = round(sqrt(abs_sq));
        bigint ans = 0;
        if (abs_sq == static_cast<long>(abs_round) * abs_round) {
            bigint abs_ans = boost::multiprecision::pow(bigint{abs_round}, N);
            ans = max(imag, -imag) * g / abs_ans;
        } else {
            bigint abs_ans = boost::multiprecision::pow(bigint{abs_sq}, N);
            bigint mag_sq = imag * imag * g * g / abs_ans;
            ans = mag_sq;
            do {
                ans = (ans + mag_sq / ans) / 2;
            } while (mag_sq / ans / ans == 0);
        }
        cout << (imag < 0 ? "-" : "") << ans / 100000 << "." << setw(5) << setfill('0') << ans % 100000 << endl;
    }();
    return 0;
}