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#include<bits/stdc++.h>
#define VAR(i,n) __typeof(n) i = (n)
#define loop(i,j,s) for(int i=j;i<s;i++)
#define loopback(i,j,s) for(int i=j;i>=s;i--)
#define foreach(i,c) for(VAR(i,(c).begin());i!=(c).end();i++)
#define pln( x ) cout << x << "\n"
#define ps( x ) cout << x << " "
#define entr cout << "\n"
#define pcnt(i) __builtin_popcount(i)
#define ll long long
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define SIZE(c) (c).size()
#define ALL(c) (c).begin(), (c).end()
using namespace std;
typedef vector<int> VI;
const int INFTY=20000000;
const int MAX=3100;
const ll MOD=1000000007;

void coutTab(int* tab,int n){
	loop(i,0,n){
		cout<<tab[i]<<" ";
	}
	cout<<"\n";
}
//------------------------------------------
bool B[MAX][MAX];
int L[MAX][MAX]; //layers
int n,k;
ll c=0;
bool can(int i,int j){
	if(B[i][j]) return false;
	if(i-1>=0&&B[i-1][j]) return true;
	if(i+1<n&&B[i+1][j]) return true;
	if(j-1>=0&&B[i][j-1]) return true;
	if(j+1<n&&B[i][j+1]) return true;
	return false;
}
bool ok(){
	loop(i,0,n){
		loop(j,0,n){
			if(B[i][j]){
				B[i][j]=false;
				if(!can(i,j)){ 
					B[i][j]=true;
					return false;
				}	
				B[i][j]=true;
			}
		}
	}
	return true;
}
void gen(int i,int str,int stc){ //number of move, start pos row, start pos
	if(i==k+1){
		if(ok()) 
		c=(c+1)%MOD;
		return;
	}
	loop(j,str,n){
		int st=(j==str ? stc : 0);
		loop(l,st,n){
			if(!B[j][l]&&L[j][l]>0){
				B[j][l]=true;
				(l==n-1 ? gen(i+1,j+1,0) : gen(i+1,j,l+1));
				B[j][l]=false;
			}
		}
	}
}
ll si(int k){
	ll d=1;
	for(ll i=2;i<k+1;i++) d*=i;
	return d;
}
int main(){
	ios_base::sync_with_stdio(0);
	int q;
	cin>>n>>k;
	char a;
	loop(i,0,n){
		loop(j,0,n){
			cin>>a;
			B[i][j]=(a=='#');
			if(B[i][j]) L[i][j]=0;
			else L[i][j]=-1;
		}
	}
	//count	layers
	loop(l,1,5){
		loop(i,0,n){
			loop(j,0,n){
				if(L[i][j]==-1){
					if(i-1>=0&&L[i-1][j]==l-1) L[i][j]=l;
					else if(i+1<n&&L[i+1][j]==l-1) L[i][j]=l;
					else if(j-1>=0&&L[i][j-1]==l-1) L[i][j]=l;
					else if(j+1<n&&L[i][j+1]==l-1) L[i][j]=l;
				} 
			}
		}
	}
	gen(1,0,0);
	pln(c);
}