MOD = 998244353
PHI = MOD - 1  # Because MOD is prime

T = int(input())
for _ in range(T):
    N, K = map(int, input().split())
    
    # Calculate exponent for 2^(N*K)
    e1 = ((N % PHI) * (K % PHI)) % PHI
    a = pow(2, e1, MOD)
    
    # Calculate exponent for 2^(K*(N-1))
    n_minus_1 = (N - 1) % PHI
    e2 = (n_minus_1 * (K % PHI)) % PHI
    b = pow(2, e2, MOD)
    
    # Compute the difference and final answer
    diff = (a - b) % MOD
    ans = (N * diff) % MOD
    print(ans)