package main

import . "fmt"
import . "os"
import bf "bufio"
import . "math/big"

func main() {
	rd:=bf.NewReader(Stdin)
	wr:=bf.NewWriter(Stdout)
	var t int
	Fscan(rd,&t)
	one:=NewInt(1)
	ten:=NewInt(10)
	mod:=NewInt(998244353)
	x,z:=new(Int),new(Int)
	for ;t>0;t-- {
		var n,m int64
		Fscan(rd,&n,&m)
		if n/m%2==0 {
			z.Exp(ten,z.SetInt64(n%m),mod)
			z.Add(z,mod).Sub(z,one).Mod(z,mod)
		} else {
			x.Exp(ten,x.SetInt64(m),mod)
			x.Add(x,one).Add(x,mod).Add(x,mod)
			z.Exp(ten,z.SetInt64(n%m),mod)
			z.Sub(x,z).Sub(z,one).Mod(z,mod)
		}
		Fprintln(wr,z)
	}
	wr.Flush()
}