t = int(input())
mod = 998244353

def power(a, n, mod):
    bi=str(format(n,"b"))
    res=1
    for i in range(len(bi)):
        res=(res*res) %mod
        if bi[i]=="1":
            res=(res*a) %mod
    return res

for i in range(t):
    n,k = map(int, input().split())
    ans = power(power(2, n, mod), k, mod)-power(power(2, n-1, mod), k, mod)
    ans *= n
    ans %= mod
    print(ans)