#include<bits/stdc++.h>
#define int long long
using namespace std;

const int maxn = 2e3 + 5;
char a[maxn][maxn];
bool vis[maxn][maxn];
int T, n, m;

struct node {
	int x, y;
	int step;
};

const int fx[] = {0, 0, 1, 0, -1};
const int fy[] = {0, 1, 0, -1, 0};

signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);

	cin >> T;

	while (T--) {
		cin >> n >> m;

		int sx, sy, ex, ey;
		for (int i = 1; i <= n; i++) {
			for (int j = 1; j <= m; j++) {
				cin >> a[i][j];
				if (a[i][j] == 'r') sx = i, sy = j;
				if (a[i][j] == 'a') ex = i, ey = j;
				vis[i][j] = 0;
			}
		}

		queue<node> q;
		q.push({sx, sy, 0});
		vis[sx][sy] = 1;

		bool flag = false;
		while (q.size() > 0) {
			node u = q.front(); q.pop();
			for (int i = 1; i <= 4; i++) {
				int tx = u.x + fx[i];
				int ty = u.y + fy[i];
				if (tx <= 0 || tx > n || ty <= 0 || ty > m) continue;
				if (a[tx][ty] == '#' || vis[tx][ty]) continue;
				if (a[tx][ty] == '@') q.push({tx, ty, u.step + 1});
				else if (a[tx][ty] == 'x') q.push({tx, ty, u.step + 2});
				else if (tx == ex && ty == ey) {
					cout << u.step + 1 << "\n";
					flag = true;
					break;
				}
				vis[tx][ty] = true;
			}
			if (flag == true) break;
		}
		
		if (!flag) cout << "Impossible\n";
	}
	
	return 0;
}

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