#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cmath>
#include<iostream>
using namespace std;
int n,m;
long long p;
char xu[50][50];
bool ever[50][50];
int getint()
{
    int res=0;
    char ch=getchar();
    while((ch<'0' || ch>'9') && ch!='-')
        ch=getchar();
    bool fan=0;
    if(ch=='-')
    {
        fan=1;
        ch=getchar();
    }
    while('0'<=ch && ch<='9')
    {
        res=res*10+ch-'0';
        ch=getchar();
    }
    if(fan)
        res=-res;
    return res;
}
void GetData()
{
    int i,j;
    m=getint();
    cin>>p;
    for(i=1;i<=n;i++)
    {
        char ch;
        scanf(" %c",&ch);
        xu[i][1]=ch;
        for(j=2;j<=m;j++)
            xu[i][j]=getchar();
    }
    for(i=1;i<=n;i+=2)
    {
        for(j=1;j<=m;j+=2)
            xu[i][j]-='0';
    }
}
bool dfs(int x,int y,long long a,long long b)
{
    if(a==p*b)
        return 1;
    ever[x][y]=1;
    int xx,yy,val;
    char opt;
    xx=x-2;
    yy=y;
    if(xx>0 && !ever[xx][yy])
    {
        opt=xu[x-1][y];
        val=xu[xx][yy];
        if(opt=='+')
        {
            if(dfs(xx,yy,a+b*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(opt=='-')
        {
            if(dfs(xx,yy,a-b*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(opt=='*')
        {
            if(dfs(xx,yy,a*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(val)
        {
            if(dfs(xx,yy,a,b*val))
            {
                ever[x][y]=0;
                return 1;
            }
        }
    }
    xx=x+2;
    yy=y;
    if(xx<=n && !ever[xx][yy])
    {
        opt=xu[x+1][y];
        val=xu[xx][yy];
        if(opt=='+')
        {
            if(dfs(xx,yy,a+b*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(opt=='-')
        {
            if(dfs(xx,yy,a-b*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(opt=='*')
        {
            if(dfs(xx,yy,a*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(val)
        {
            if(dfs(xx,yy,a,b*val))
            {
                ever[x][y]=0;
                return 1;
            }
        }
    }
    xx=x;
    yy=y-2;
    if(yy>0 && !ever[xx][yy])
    {
        opt=xu[x][y-1];
        val=xu[xx][yy];
        if(opt=='+')
        {
            if(dfs(xx,yy,a+b*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(opt=='-')
        {
            if(dfs(xx,yy,a-b*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(opt=='*')
        {
            if(dfs(xx,yy,a*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(val)
        {
            if(dfs(xx,yy,a,b*val))
            {
                ever[x][y]=0;
                return 1;
            }
        }
    }
    xx=x;
    yy=y+2;
    if(yy<=m && !ever[xx][yy])
    {
        opt=xu[x][y+1];
        val=xu[xx][yy];
        if(opt=='+')
        {
            if(dfs(xx,yy,a+b*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(opt=='-')
        {
            if(dfs(xx,yy,a-b*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(opt=='*')
        {
            if(dfs(xx,yy,a*val,b))
            {
                ever[x][y]=0;
                return 1;
            }
        }
        else if(val)
        {
            if(dfs(xx,yy,a,b*val))
            {
                ever[x][y]=0;
                return 1;
            }
        }
    }
    ever[x][y]=0;
    return 0;
}
void DoIt()
{
    int i,j;
    for(i=1;i<=n;i+=2)
    {
        for(j=1;j<=m;j+=2)
        {
            if(dfs(i,j,xu[i][j],1))
            {
                printf("Possible\n");
                return;
            }
        }
    }
    printf("Impossible\n");
}
void f()
{
    GetData();
    DoIt();
}
int main()
{
    int T=getint();
    while((scanf("%d",&n))!=EOF)
        f();
    return 0;
}