#include <iostream>
#define int long long
using namespace std;

int powmod(int a, int n, int mod) {
	if (n == 0) return 1;
	if (n % 2 == 0) return powmod((a * a) % mod, n / 2, mod);
	return (a * powmod(a, n - 1, mod)) % mod;
}

int mod = 998244353;

signed main() {
	int t; cin >> t;
	while (t--) {
		int n, k;
		cin >> n >> k;
		
		//n (2^(nk) - 2^((n-1)k))
		int res1 = powmod(2, n * k, mod);
		int res2 = powmod(2, (n - 1) * k, mod);
		int res3 = (res1 - res2 + mod) % mod;
		int ans = n * res3 % mod;
		cout << ans << endl;
	}
	return 0;
}