#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;
typedef long double ld;
typedef unsigned int uint;
typedef vector<int> vi;
typedef vector< vector <int> > vvi;
typedef pair<int, int> pii;
typedef pair < pair < int, int >, int > piii;
typedef pair < pair <int, int > , pair <int, int> > piiii;
typedef pair<ll, ll> pll;
typedef vector<bool> vb;
typedef vector<char> vc;
typedef vector<string> vs;
 
#define FOR(i,a,b) for(int i = a; i < b; i ++)
#define RFOR(i,a,b) for(int i = a-1; i >= b; i --)
#define all(a) a.begin(), a.end()
#define endl '\n';
#define sz(x) (int)(x).size()
 
#define mp make_pair
#define pb push_back
#define ff first
#define ss second
 
template <typename T>
void pr(vector<T> &v) {
    FOR(i, 0, sz(v)) cout << v[i] << " ";
    cout << endl;
}
template <typename T>
void pr(vector<vector<T> > &v) {
    FOR(i, 0, sz(v)) { pr(v[i]); }
}
template <typename T>
void re(T &x) {
    cin >> x;
}
template <typename T>
void re(vector<T> &a) {
    FOR(i, 0, sz(a)) re(a[i]);
}
template <class Arg, class... Args>
void re(Arg &first, Args &... rest) {
    re(first);
    re(rest...);
}
template <typename T>
void pr(T x) {
    cout << x << endl;
}
template <class Arg, class... Args>
void pr(const Arg &first, const Args &... rest) {
    cout << first << " ";
    pr(rest...);
    cout << endl;
}
void ps() { cout << endl; }
template<class T, class... Ts>
void ps(const T& t, const Ts&... ts) {
    cout << t; if (sizeof...(ts)) cout << " "; ps(ts...);
}
 
const ll MOD  =  998244353;
#define inf 1e18;
#define INF INT_MAX;
 
long double PI = 4*atan(1);
long double eps = 1e-12;


ld solve() {
    ld l1,l2,a,b; cin >> l1 >> l2 >> a >> b;
    a *= (PI/180);
    b *= (PI/180);
    ld ans = (l1 + l2) * (l1 + l2) *  a + l2 * l2 *  b;
    if(b <= PI* 0.5) {
        return ans;
    }

    ld d = 0;
    ld phi = 0;

    // perp doesn't reach
    if(l2 <= l1 * cos(PI - b)) {
        d = sqrt(l1 * l1 + l2 * l2 - 2 * l1 * l2 * cos(PI - b));
        phi = asin(l2 / d * sin(PI - b));
    } else {
        phi = b - PI * 0.5;
        d = l1 * cos(phi);
    }

    if(2*a >= phi) {
        ans += l1 * d * sin(phi);
        ans -= d * d * phi;
        return ans;
    } 

    ld d2 = 0;
    ld d3 = 0;

   // cout << d << " " << d2 << " " << d3 << endl;
    // perp doesn't reach
  //  cout << ans << endl;
    if(l2 <= l1 * cos(PI - b)) {
       // cout << "HI" << endl;
        d2 = sin(b-phi)/sin(PI - 2*a - b + phi) * d;
        d3 = sin(b-phi)/sin(PI - b + 2 * a) * d;
    } else {
        d2 = d/cos(2*a);
        d3 = d/cos(phi - 2*a);
    }

    ans += d * d2 * sin(2*a);
    ans -= d * d * 2*a;
    ans += d2 * l1 * sin(phi - 2*a);
    ans -= d * d3 * sin(phi - 2*a);
    return ans;
}

int main() {
    //auto start = chrono::high_resolution_clock::now();
    ios_base::sync_with_stdio(0);cin.tie(0);
    // freopen("promote.in", "r", stdin);
	// freopen("promote.out", "w", stdout);
    #ifdef DEBUG
      freopen("input.txt", "r", stdin);
      freopen("output.txt", "w", stdout);
    #endif 

    int t; cin >> t;
    FOR(tcase,0,t) {
        cout << setprecision(16) << solve() << endl;
    }
    // cout << 100000 << endl;
    // FOR(i,0,100000) {
    //     cout << "100 10 76 179" << endl;
    // }


    // auto stop = chrono::high_resolution_clock::now();
    // auto duration = chrono::duration_cast<chrono::microseconds>(stop - start);
    // cout << duration.count() << endl;
    //cin.close();
    //cout.close();
}