#include<bits/stdc++.h>

using namespace std;
typedef long long ll;
const double eps=1e-8;
int w[100010];
int idx[100010];
int a,b,r,x;
double check(double x) {
	double s=(double)x*acos(-1)/180;
	double res=a*cos(s)+b*sin(s)-r*sin(s)*tan(s);
	return res;
}

int main() {
	int T;
	cin>>T;
	
	while(T--) {
		
		cin>>a>>b>>r>>x;
		double res=sqrt((r+a)*(r+a)+b*b);
		
		double s=(double)x*acos(-1)/180;
		if((double)b/(a+r)<=tan(s)||x>=90) 
			printf("%.15f\n",res-r);
		else {
			double s1=(double)b/(a+r);
			double x1=atan(s1)-(double)x*acos(-1)/180;
			printf("%.15f\n",res*cos(x1)-r);
			
			// printf("%.15f\n",check(l));
		}
	}
	return 0;
}