C++ :

#include <stdio.h>

const int MOD = int(1e9) + 7;

int main()
{
  int casc;
  scanf("%d", &casc);
  for (int casi = 1; casi <= casc; casi++) {
    int n, k;
    scanf("%d %d", &k, &n);
    long long a = 1;
    long long b = 1;
    for (int i = 0; i < 2 * k; i++) {
      a = a * n % MOD;
      b = b * (n + 1) % MOD;
    }
    int res = (a + b - 1 + MOD) % MOD;
    printf("%d\n", res);
  }
  return 0;
}