#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<queue>

#define ll long long
#define inf 1e9
#define eps 1e-10
#define md
#define N 55
using namespace std;
struct data { int x,y,k; double dis; };
struct cmp
{
    bool operator () (data A,data B) { return A.dis>B.dis; }
};
priority_queue<data,vector<data>,cmp> q;
double dis[N][N][N];
bool vis[N][N][N];
int a[N][N];
char st[N];
int n,m,K,sx,sy,tx,ty;
int lx[4]={-1,0,1,0},ly[4]={0,-1,0,1};
void dj()
{
    for (int i=1;i<=n;i++)
      for (int j=1;j<=m;j++)
        for (int k=0;k<=K;k++)
          dis[i][j][k]=inf;
    memset(vis,0,sizeof(vis));
    while (!q.empty()) q.pop();
    dis[sx][sy][K]=0;
    data hd,ins; hd.x=sx; hd.y=sy; hd.k=K; hd.dis=0; q.push(hd); 
    while (!q.empty())
    {
        hd=q.top(); q.pop();
        int i=hd.x,j=hd.y,k=hd.k; double len=dis[i][j][k]; //printf("%d %d %d a:%d dis: %.3lf\n",i,j,k,a[i][j],len);
        if (vis[i][j][k]) continue;
        vis[i][j][k]=1;
        if (i==tx&&j==ty&&k>=1) { printf("%.2lf\n",len); return; }
        if (k==1) continue;
        for (int p=0;p<=3;p++)
        {
            int x=i+lx[p],y=j+ly[p];
            if (x<1||y<1||x>n||y>m||a[x][y]==-1) continue;
            double ds=len+(double)abs(a[i][j]-a[x][y])/k; //printf("    : %d %d %d a:%d dis:%.3lf\n",x,y,k-1,a[x][y],ds);
            if (ds<dis[x][y][k-1])
            {
                ins.x=x; ins.y=y; ins.k=k-1; ins.dis=ds;
                dis[x][y][k-1]=ds;
                q.push(ins);
            }
        }
    }
    printf("No Answer\n");
}

int main()
{
    int tt;
    scanf("%d",&tt);
    while (tt--)
    {
        scanf("%d%d%d",&n,&m,&K);
        for (int i=1;i<=n;i++)
        {
            scanf("%s",st+1);
            for (int j=1;j<=m;j++)
            {
                if (st[j]=='#') a[i][j]=-1; else a[i][j]=st[j]-'0';
            }
        }
        scanf("%d%d%d%d",&sx,&sy,&tx,&ty);
        dj();
    }
    return 0;
}