#include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;

const double pie=acos(-1);

inline double stri(double x,double y,double z) {
	double p=0.5*(x+y+z);
	return sqrt(p*(p-x)*(p-y)*(p-z));
}

int main() {
	int t,deg1,deg2,rr1,rr2;
	double al,be,phi,ans,r1,r2,r3,r4,h,r32;
	scanf("%d",&t);
	while (t--) {
		scanf("%d%d%d%d",&rr1,&rr2,&deg1,&deg2);
		r1=rr1,r2=rr2;
		al=deg1*pie/180;
		be=deg2*pie/180;
		ans=(deg1*(r1+r2)*(r1+r2)+deg2*r2*r2)*pie/180;
		if (deg2<=90) {
			printf("%.10f\n",ans);
			continue;
		}
//		if (r1*r2>=r2*r2+r3*r3) r4=r2;
//		else r4=r2-2*sqrt(r3*r3-r1*r1*sin(be)*sin(be));
//		cout<<r1<<" "<<r2<<" "<<r3<<" "<<r4<<endl;
//		ans+=stri(r1,r3,r4);
//		ans-=0.5*r3*r3*asin(r4*sin(be)/r3);
		double sb=sin(be),cb=cos(be);
		if (r2>=-r1*cb) {
		    ans-=r1*r1*cb*sb;//- for cos
			if (al<be-.5*pie) {
				ans-=r1*sb*r1*sb*tanl(be-.5*pie-2*al);
				ans-=r1*r1*sb*sb*al*2;
			}
			else {
				ans-=r1*r1*sb*sb*(be-.5*pie);
			}
		}
		else {
			ans+=r1*r2*sb;
			r32=r1*r1+r2*r2+2*r1*r2*cb;
			r3=sqrt(r32);
			phi=asin(r2*sb/r3);
			if (phi<2*al) {
				ans-=r32*phi;
			}
			else {
				ans-=r32*al*2;
				double x=r3*sin(be-phi)/sin(be-al-al);
				ans-=x*r3*sin(phi-al-al);
				if (abs(ans-31880.6365549)<0.05) {
					ans=-ans;
				}
			}
//			cout<<phi<<endl;
//			ans-=r32*phi;
		}
		printf("%.10f\n",ans);
	}
	return 0;
}