//https://cdn.luogu.com.cn/upload/image_hosting/bce60lzi.png
//https://cdn.luogu.com.cn/upload/image_hosting/30e80xrq.png
//https://cdn.luogu.com.cn/upload/image_hosting/kejvnuf4.png
#include<cstdio>
#include<cmath>
using namespace std;
const long double PI=acosl(-1);
int T;long double l1,l2,l3,Alpha,Beta,Gamma,t,ans;
inline long double calc(long double x,long double Alpha,long double Beta){
	return x*x*sinl(Alpha)*sinl(Beta)/sinl(PI-Alpha-Beta);
}
int main(){
	for(scanf("%d",&T);T--;printf("%.9Lf\n",ans)){
		scanf("%Lf%Lf%Lf%Lf",&l1,&l2,&Alpha,&Beta);Alpha=Alpha/180*PI;t=Beta=Beta/180*PI;
		if(l1<l2){
			Gamma=Alpha-asinl(l1*sinl(Alpha)/l2);
			if(PI-Beta<Gamma) Beta=PI-Gamma;
		}
		ans=(l1+l2)*(l1+l2)*Alpha+l2*l2*Beta;
		if(l1<l2&&PI-t<Gamma) Beta=t,t=l1*sinl(Alpha)/sinl(Alpha-(PI-Beta)),ans+=l2*t*sinl(Gamma-(PI-Beta));
		if(Beta>PI/2){
			if(l2>l1*cosl(PI-Beta)) l2=l1*cosl(PI-Beta),l3=l1*sinl(Beta);
			else l3=sqrtl(l1*l1+l2*l2-2*l1*l2*cosl(PI-Beta));
			Gamma=asinl(l2*sinl(Beta)/l3);
			if(Gamma<2*Alpha) ans+=l1*l2*sinl(Beta)-l3*l3*asinl(l2*sinl(Beta)/l3);
			else ans+=l1*l2*sinl(Beta)-l1*l3*sinl(Gamma-2*Alpha)-l3*l3*2*Alpha+
			l1*l3*sinl(Gamma-2*Alpha)-calc(l3,Gamma-2*Alpha,asinl(l1*sinl(Beta)/l3));
		}
	}
	return 0;
}