10056 - What is the Probability ?

/*
简单概率题，一次AC
*/
#include <cstdio>
int main()
{
	//freopen("f://data.in", "r", stdin);
	int T;
	scanf("%d", &T);
	while(T--)
	{
		int N, I;
		double p;
		scanf("%d %lf %d", &N, &p, &I);
		double q, t;
		int i;
		for(i = 0, t = 1; i < N; ++ i)
			t *= (1 - p);
		for(q = p, i = 1; i < I; ++ i)
			q *= (1 - p);
		double ans = q;
		while(q > 1e-6)
		{
			q *= t;
			ans += q;
		}
		printf("%.4lf\n", ans);
	}
	return 0;
}