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

using ld = long double;

ld f(long x, ld Q, ld R, int remain, ld p) {
    ld a = (remain - x) * (Q - (1.0 - p) * R);   // もみ消す
    ld b = Q * ((1.0 - pow(p, x)) / (1.0 - p));  // クビになる(ゼロ除算に注意)
    return a + b;
}
ld g(long x, ld Q, ld R, long remain, ld p) {
    ld a = -Q + (1 - p) * R;
    ld b = Q * pow(p, x);
    return a + b;
}
ld h(long t, long N, ld X, ld Y, ld P, ld Q, ld R) {
    long skill = X + t * Y;
    ld p = 1.0 - 1.0 / skill;
    long remain = N - t;
    if (skill == 1) {  // 必ず卵をかけてしまう場合
        if (remain == 1) {
            return P * t + Q;
        } else {
            return P * t + (Q - R) * (remain - 1) + Q;
        }
    }
    ld u = 0;
    if ((1.0 - p) * R >= Q) {
    	u = remain;
    } else {
    	u = min(remain, max(0L, long(log(1.0 - (1 - p) * R / Q) / log(p) + 1.0)));
    }
    return P * t + f(u, Q, R, remain, p);
}
int main(void) {
    auto solve = []() {
        long N, X, Y;
        cin >> N >> X >> Y;
        ld P, Q, R;
        cin >> P >> Q >> R;
        long l = 0, r = N;
        while (r - l > 3) {
            long m1 = l + (r - l) / 3;
            long m2 = r - (r - l) / 3;
            ld v1 = h(m1, N, X, Y, P, Q, R);
            ld v2 = h(m2, N, X, Y, P, Q, R);
            if (v1 < v2) {
                l = m1;
            } else {
                r = m2;
            }
        }
        ld ans = 0;
        for (long t = l; t <= r; ++t) {
            ans = max(ans, h(t, N, X, Y, P, Q, R));
        }
        cout << fixed << setprecision(10) << ans << endl;
    };
    int T;
    cin >> T;
    for (int i = 0; i < T; i++) {
        solve();
    }
}