1 #include<cstdio>
 2 #include<algorithm>
 3 #include<cstring>
 4 #include<queue>
 5 #include<iostream>
 6 #include<stack>
 7 #include<map>
 8 #include<cmath>
 9 #include<string>
10 using namespace std;
11 #define N 1000000
12 struct Point{
13     double x;
14     double y;
15 }point[110];
16 double area2(double x0, double y0 , double x1, double y1, double x2, double y2)
17 {
18     return fabs(x0*y1+x2*y0+x1*y2-x2*y1-x0*y2-x1*y0);
19 }
20 int main(){
21     int n;
22     int tcase;
23     scanf("%d", &tcase);
24     while(tcase--){
25         double minn = 10000005;
26         bool flag = false;
27         scanf("%d", &n);
28         for(int i = 0; i < n; i++){
29             scanf("%lf%lf", &point[i].x, &point[i].y);
30         }
31         if(n >= 3){
32             for(int i = 0; i < n-2; i++){
33                 for(int j = i+1; j < n-1; j++){
34                     for(int k = j+1; k < n; k++){
35                         double x1, x2, x3, y1, y2, y3;
36                         x1 = point[i].x; y1 = point[i].y;
37                         x2 = point[j].x; y2 = point[j].y;
38                         x3 = point[k].x; y3 = point[k].y;
39                         double num = area2(x1, y1, x2, y2, x3, y3);
40                         num /= 2.0;
41                         if(num < minn && num != 0){
42                             minn = num;
43                             flag = true;
44                         }
45                     }
46                 }
47             }
48         }
49         if(flag)
50             printf("%.2lf\n", minn);
51         else
52             printf("Impossible\n");
53     }
54     return 0;
55 }