#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<vector>
#include<set>
#include<deque>
#define LL long long
#define INF 0X7FFFFFFF
using namespace std;
int N,M,K,T,x1,yy,x2,y2;
char s[55];
double cost[55][55][55];
int map[55][55];
inline void init()
{
    int i,j,k;
    for(i=1;i<=N;i++)
        for(j=1;j<=M;j++)
            for(k=1;k<=50;k++)
            cost[i][j][k]=INF*1.0;
}
struct Node
{
    int x,y;
    double cos;
    int douzhi;
};
inline void BFS()
{
    deque<Node> Q;int x,y,cha;double tmp;
    Node temp,nex;temp.x=x1;temp.y=yy;temp.cos=0;temp.douzhi=K;cost[x1][yy][K]=0.0;
    Q.push_back(temp);
    while(!Q.empty())
    {
        temp=Q.at(0);Q.pop_front();
        if(temp.x-1>0&&temp.douzhi>1&&map[temp.x-1][temp.y]!=-1)
        {
            x=temp.x-1;cha=abs(map[x][temp.y]-map[temp.x][temp.y]);
            tmp=cha*1.0/temp.douzhi;
            if(temp.cos+tmp<cost[x][temp.y][temp.douzhi-1])
            {
                cost[x][temp.y][temp.douzhi-1]=temp.cos+tmp;
                nex.x=temp.x-1;nex.y=temp.y;nex.douzhi=temp.douzhi-1;nex.cos=temp.cos+tmp;
                Q.push_back(nex);
            }
        }
        if(temp.x+1<=N&&temp.douzhi>1&&map[temp.x+1][temp.y]!=-1)
        {
            x=temp.x+1;cha=abs(map[x][temp.y]-map[temp.x][temp.y]);
            tmp=cha*1.0/temp.douzhi;
            if(temp.cos+tmp<cost[x][temp.y][temp.douzhi-1])
            {
                cost[x][temp.y][temp.douzhi-1]=temp.cos+tmp;
                nex.x=temp.x+1;nex.y=temp.y;nex.douzhi=temp.douzhi-1;nex.cos=temp.cos+tmp;
                Q.push_back(nex);
            }
        }
        if(temp.y-1>0&&temp.douzhi>1&&map[temp.x][temp.y-1]!=-1)
        {
            y=temp.y-1;cha=abs(map[temp.x][y]-map[temp.x][temp.y]);
            tmp=cha*1.0/temp.douzhi;
            if(temp.cos+tmp<cost[temp.x][y][temp.douzhi-1])
            {
                cost[temp.x][y][temp.douzhi-1]=temp.cos+tmp;
                nex.x=temp.x;nex.y=temp.y-1;nex.douzhi=temp.douzhi-1;nex.cos=temp.cos+tmp;
                Q.push_back(nex);
            }
        }    
        if(temp.y+1<=M&&temp.douzhi>1&&map[temp.x][temp.y+1]!=-1)
        {
            y=temp.y+1;cha=abs(map[temp.x][y]-map[temp.x][temp.y]);
            tmp=cha*1.0/temp.douzhi;
            if(temp.cos+tmp<cost[temp.x][y][temp.douzhi-1])
            {
                cost[temp.x][y][temp.douzhi-1]=temp.cos+tmp;
                nex.x=temp.x;nex.y=temp.y+1;nex.douzhi=temp.douzhi-1;nex.cos=temp.cos+tmp;
                Q.push_back(nex);
            }
        }                    
    } 
}
int main()
{
    int i,j;
    double ans;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d%d%d",&N,&M,&K);
        init();ans=INF*1.0;
        for(i=1;i<=N;i++)
        {
            scanf("%s",s);
            for(j=0;j<M;j++)
            {
                if(s[j]=='#')
                    map[i][j+1]=-1;
                else
                    map[i][j+1]=s[j]-48;
            }
        }
        scanf("%d%d",&x1,&yy);
        scanf("%d%d",&x2,&y2);
        BFS();
        for(i=1;i<=K;i++)
            ans=min(cost[x2][y2][i],ans);
        if(ans>INF*1.0-10)
            printf("No Answer\n");
        else
            printf("%.2lf\n",ans);
    }
    return 0;
}