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#include <iostream>
#include <vector>
using namespace std;

long long p[3000][3000];
long long n, k;
long long result = 0;

class Point {
public:
	int x, y;
	Point(int x, int y) {
		this -> x = x;
		this -> y = y;
	}
	Point left()  { return Point(this -> x-1, this -> y); }
	Point right() { return Point(this -> x+1, this -> y); }
	Point bottom(){ return Point(this -> x,   this -> y-1); }
	Point top()   { return Point(this -> x,   this -> y+1); }
};

void addToResult(long long x) {
	result %= 1000000007;
	x %= 1000000007;
	result += x;
	if(result < 0) result *= -1;
	result %= 1000000007;
}

int isCorner(int x, int y, int v) {
	if(p[x][y] == v) {
		int ctr_crn = 0;
		if( ((x > 0 && p[x-1][y] == v-1) && (y > 0 && p[x][y-1] == v-1)) ) ctr_crn++;
		if(	((x > 0 && p[x-1][y] == v-1) && (y < n-1 && p[x][y+1] == v-1)) ) ctr_crn++;
		if(	((x < n-1 && p[x+1][y] == v-1) && (y < n-1 && p[x][y+1] == v-1)) ) ctr_crn++;
		if(	((x < n-1 && p[x+1][y] == v-1) && (y > 0 && p[x][y-1] == v-1)) ) ctr_crn++;

		if(ctr_crn == 1) return 1;
		if(ctr_crn == 2) return 2;
		if(ctr_crn > 2) return 4;
	}
	return 0;
}

int isLine(int x, int y, int v) {
	if(p[x][y] == v) {
		int ctr_ln = 0;
		if( (x > 0 && p[x-1][y] == v-1) && (x < n-1 && p[x+1][y] == v-1) ) ctr_ln++;
		if(	(y > 0 && p[x][y-1] == v-1) && (y < n-1 && p[x][y+1] == v-1) ) ctr_ln++;

		if(ctr_ln == 1) return 1;
		if(ctr_ln > 1) return 2;
	}
	return 0;
}

bool isValid(long long x, long long y, int busy) {
	if(x < 0 || x >= n || y < 0 || y >= n)  return false;
	if(p[x][y] == busy) return false;
	if( (x > 0 && p[x-1][y] == busy) || (x < n-1 && p[x+1][y] == busy) || (y > 0 && p[x][y-1] == busy) || (y < n-1 && p[x][y+1] == busy) ) {
			return true;
	}
	return false;
}

bool isValid(long long x, long long y, int busy, int notValidFor) {
	for(int i = notValidFor; i > 0; i--) {
		if(p[x][y] == notValidFor || isValid(x, y, i)) {
			return false;
		}
	}
	return isValid(x, y, busy);
}

long long s(long long n, long long k) {
	if(k <= 0 || k > n) return 0;
	long long result = 1, div = 1;
	for(long long i = n; i > n - k; i--) {
		result *= i;
	}
	for(int i = 1; i <= k; i++) {
		div *= i;
	}

	result /= div;
	return result;
}

void inspectPoint(int x, int y, int depth, long long validFieldsCount) {
	if(depth <= k) {
		p[x][y] = depth;
		if(depth == 3) addToResult(validFieldsCount - 1);
		if(depth == 4) addToResult(validFieldsCount - 2);
		if(isValid(x - 1, y, depth, depth - 1)) {

			if(depth == k) {
				addToResult(1);
			}
			inspectPoint(x - 1, y, depth + 1, validFieldsCount);
		}
		if(isValid(x + 1, y, depth, depth - 1)) {

			if(depth == k) {
				addToResult(1);
			}
			inspectPoint(x + 1, y, depth + 1, validFieldsCount);
		}
		if(isValid(x, y - 1, depth, depth - 1)) {

			if(depth == k) {
				addToResult(1);
			}
			inspectPoint(x, y - 1, depth + 1, validFieldsCount);
		}
		if(isValid(x, y + 1, depth, depth - 1)) {

			if(depth == k) {
				addToResult(1);
			}
			inspectPoint(x, y + 1, depth + 1, validFieldsCount);
		}
	}
}

int main() {
	vector<Point> validPoints;
	cin >> n >> k;

	for(long long i = 0; i < n; i++) {
		string s;
		cin >> s;
		for(long long j = 0; j < n; j++) {
			if(s[j] == '.') p[i][j] = 0;
			else p[i][j] = 1;
		}
	}

	long long validFieldsCount = 0;
	for(long long x = 0; x < n; x++) {
		for(long long y = 0; y < n; y++) {
			if(isValid(x, y, 1)) {
				validPoints.push_back(Point(x, y));
				validFieldsCount++;
			}
		}
	}

	if(validFieldsCount >= k) {
		addToResult(s(validFieldsCount, k));
	}

	for(Point point : validPoints) {
		inspectPoint(point.x, point.y, 2, validFieldsCount);
	}

	if(k >= 3) {
		for(int x = 0; x < n; x++) {
			for(int y = 0; y < n; y++) {
				addToResult(isCorner(x, y, 3));
				addToResult(isLine(x, y, 3));
			}
		}
	}

	if(k >= 4) {
		for(int x = 0; x < n; x++) {
			for(int y = 0; y < n; y++) {
				addToResult(isCorner(x, y, 4));
				addToResult(isLine(x, y, 4));
			}
		}
	}

	cout << result;

	return 0;
}