import sys; input = sys.stdin.buffer.readline
sys.setrecursionlimit(10**7)
from collections import defaultdict
con = 998244353; INF = float("inf")

def getlist():
	return list(map(int, input().split()))

#処理内容
def main():
	T = int(input())
	for _ in range(T):
		N, K = getlist()
		ans = pow(2, N * K, con) - pow(2, (N - 1) * K, con)
		ans *= N
		ans %= con
		print(ans)



if __name__ == '__main__':
	main()