Q=int(input())
for _ in range(Q):
  N,M=map(int,input().split())
  mod=998244353
  k=N//M
  x=N%M
  p=pow(10,x,mod)
  if k%2==0:
    result=p-1
    result%=mod
  else:
    result=-p-1
    result%=mod
  print(result)