mod = 998244353
eps = 10**-9


def main():
    import sys
    input = sys.stdin.readline

    for _ in range(int(input())):
        N, K = map(int, input().split())
        print(((pow(2, N*K, mod) * N)%mod - (pow(2, (N-1)*K, mod) * N)%mod)%mod)


if __name__ == '__main__':
    main()