T = int(input())

MOD = 998244353
for _ in range(T):
    N, M = map(int, input().split())
    N %= (M*2)
    ans = 0
    if N <= M:
        for _ in range(N):
            ans = ans*10+9
            ans %= MOD
    else:
        for _ in range(M*2-N):
            ans = ans*10+9
            ans %= MOD
        for _ in range(N%M):
            ans = ans*10
            ans %= MOD
    print(ans)