#include<bits/stdc++.h>
using namespace std;
#define FOR(i,s,t) for(int i=(s),_t=(t); i<=_t; ++i)
#define DOR(i,s,t) for(int i=(s),_t=(t); i>=_t; --i)
typedef double db;
typedef long long ll;
struct Point {
    ll x,y;
    Point operator +(const Point &s) const{
        return {x+s.x,y+s.y};
    }
    Point operator -(const Point &s) const{
        return {x-s.x,y-s.y};
    }
    Point normal() const{
        return {-y,x};
    }
    db Len() const{
        return hypot(x,y);
    }
    ll Len2() const{
        return x*x+y*y;
    }
};
ll det(Point a,Point b) {
    return a.x*b.y-a.y*b.x;
}
ll dot(Point a,Point b) {
    return a.x*b.x+a.y*b.y;
}
const int N=105;
vector<Point> a[N];
db mn[N];
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout << fixed << setprecision(9);
    int n,m;
    cin >> n >> m;
    FOR(i,1,n) {
        int K;
        cin >> K;
        while(K--) {
            ll x,y;
            cin >> x >> y;
            a[i].push_back({x,y});
        }
        mn[i]=1e9;
    }
    while(m--) {
        Point s,t;
        db hs,ht;
        cin >> s.x >> s.y >> hs;
        cin >> t.x >> t.y >> ht;
        Point d=(t-s).normal();
        FOR(i,1,n) {
            db r=0;
            for(auto p: a[i]) {
                if(det(d,p-s)>0 || det(d,p-t)<0) r=1e9;
                else {
                    db u=dot(p-s,t-s)/(t-s).Len();
                    db v=sqrt(max(0.0,(p-s).Len2()-u*u));
                    db h=hs+(ht-hs)*u/(t-s).Len();
                    r=max(r,atan(v/h));
                }
            }
            mn[i]=min(mn[i],r);
        }
    }
    db pi=acos(-1);
    db r=mn[1];
    FOR(i,2,n) r=max(r,mn[i]);
    if(r>1e8) cout << "impossible\n";
    else cout << r/pi*180 << '\n';
    return 0;
}