#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#define ll long long
#define mst(a,x) memset(a,x,sizeof(a))
using namespace std;

int n, m, k;
const int N = 55;
const int INF = 1e9 + 5;
const int dx[4] = {-1, 1, 0, 0};
const int dy[4] = {0, 0, -1, 1};
int x1, Y1, x2, y2;
double dp[N][N][N], ans;
char a[N][N];

bool inmap(int x, int y)
{
    return x >= 0 && x < n && y >= 0 && y < m;
}

int main()
{
    int T, x, y;
    
    scanf("%d", &T);
    while(T--)
    {
        scanf("%d%d%d", &n, &m, &k);
        for(int i = 0; i < n; i++) scanf("%s", a[i]);
        scanf("%d%d%d%d", &x1, &Y1, &x2, &y2);
        x1--; Y1--; x2--; y2--;
        if(!k)
        {
            puts("No Answer");
            continue;
        }

        if(x1 == x2 && Y1 == y2)
        {
            puts("0.00");
            continue;
        }

        for(int i = 0; i < n; i++)
            for(int j = 0; j < m; j++)
                dp[0][i][j] = INF;
        dp[0][x1][Y1] = 0;
        ans = INF;
        for(int t = 1; t < k; t++)
            for(int i = 0; i < n; i++)
                for(int j = 0; j < m; j++)
                {
                    dp[t][i][j] = INF;
                    for(int p = 0; p < 4; p++)
                    {
                        x = i + dx[p];
                        y = j + dy[p];
                        if(!inmap(x, y) || a[x][y] == '#' || a[i][j] == '#') continue;
                        dp[t][i][j] = min(dp[t][i][j], dp[t - 1][x][y] + fabs(1.0*(a[i][j] - a[x][y])) / (k - t + 1));
                    }
                    if(i == x2 && j == y2) ans = min(ans, dp[t][i][j]);
                }
        if(ans > 1e9)
            puts("No Answer");
        else 
            printf("%.2lf\n", ans);
    }
    return 0;
}