#include<bits/stdc++.h>
#pragma GCC optimize(3)
using namespace std;
namespace my_std{
	#define ll long long
	#define bl bool
	ll my_pow(ll a,ll b,ll mod){
		ll res=1;
		if(!b) return 1;
		while(b){
			if(b&1) res=(res*a)%mod;
			a=(a*a)%mod;
			b>>=1;
		}
		return res;
	}
	ll qpow(ll a,ll b){
		ll res=1;
		if(!b) return 1;
		while(b){
			if(b&1) res*=a;
			a*=a;
			b>>=1;
		}
		return res;
	}
	#define db double
	#define pf printf
	#define pc putchar
	#define fr(i,x,y) for(register ll i=(x);i<=(y);i++)
	#define pfr(i,x,y) for(register ll i=(x);i>=(y);i--)
	#define go(u) for(ll i=head[u];i;i=e[i].nxt)
	#define enter pc('\n')
	#define space pc(' ')
	#define fir first
	#define sec second
	#define MP make_pair
	#define il inline
	#define inf 8e18
	#define random(x) rand()*rand()%(x)
	#define inv(a,mod) my_pow((a),(mod-2),(mod))
	il ll read(){
		ll sum=0,f=1;
		char ch=0;
		while(!isdigit(ch)){
			if(ch=='-') f=-1;
			ch=getchar();
		}
		while(isdigit(ch)){
			sum=sum*10+(ch^48);
			ch=getchar();
		}
		return sum*f;
	}
	il void write(ll x){
		if(x<0){
			x=-x;
			pc('-');
		}
		if(x>9) write(x/10);
		pc(x%10+'0');
	}
	il void writeln(ll x){
		write(x);
		enter;
	}
	il void writesp(ll x){
		write(x);
		space;
	}
}
using namespace my_std;
#define mod 998244353
ll T,n,p[100010],c[100010],sum[100010],G[800080],g=3,rev[800080],lim=1;
struct node{
	ll x,y;
}F[800080],a[800080],b[800080];
node operator+(const node &x,const node &y){
	return (node){(x.x+y.x)%mod,(x.y+y.y)%mod};
}
node operator-(const node &x,const node &y){
	return (node){(x.x-y.x+mod)%mod,(x.y-y.y+mod)%mod};
}
node operator+(const node &x,const ll &y){
	return (node){x.x,(x.y+y)%mod};
}
node operator-(const node &x,const ll &y){
	return (node){x.x,(x.y-y+mod)%mod};
}
node operator*(const node &x,const ll &y){
	return (node){x.x*y%mod,x.y*y%mod};
}
void init(ll nn){
	lim=1;
	while(lim<(nn<<1)) lim<<=1;
	fr(i,0,lim-1) rev[i]=(rev[i>>1]>>1)|((i&1)?(lim>>1):0);
}
void NTT(node *A,ll t){
	fr(i,0,lim-1) if(i<rev[i]) swap(A[i],A[rev[i]]);
	for(ll i=1;i<lim;i<<=1){
		ll Wn=my_pow(g,(mod-1)/(i<<1),mod);
		for(ll j=0;j<lim;j+=(i<<1)){
			ll w=1;
			fr(k,0,i-1){
				node tmp1=A[j+k],tmp2=A[j+k+i];
				A[j+k]=tmp1+tmp2*w;
				A[j+k+i]=tmp1-tmp2*w;
				w=w*Wn%mod;
			}
		}
	}
	if(t==-1){
		reverse(A+1,A+lim);
		ll tmp=inv(lim,mod);
		fr(i,0,lim-1) A[i]=A[i]*tmp;
	}
}
void solve(ll l,ll r){
	if(l==r){
		if(l>n||!l) return;
		F[l]=F[l]*(mod+1-p[l-1]);
		F[l]=F[l]*inv(sum[l],mod);
		F[l]=F[l-1]-c[l-1]-F[l];
		F[l]=F[l]*inv(p[l-1],mod);
		return;
	}
	ll mid=(l+r)>>1;
	solve(l,mid);
	init(r-l+1);
	fr(i,0,lim-1) a[i]=b[i]=(node){0,0};
	fr(i,l,mid) a[i-l]=F[i];
	fr(i,mid+1,r) a[i-l]=(node){0,0};
	fr(i,l,r) b[i-l]=(node){0,G[i-l]};
	NTT(a,1);
	NTT(b,1);
	fr(i,0,lim) a[i]=a[i]*b[i].y;
	NTT(a,-1);
	fr(i,mid+1,r) F[i]=F[i]+a[i-l];
	solve(mid+1,r);
}
int main(){
	T=read();
	while(T--){
		n=read();
		fr(i,0,n-1){
			p[i]=read()*inv(100,mod)%mod;
			c[i]=read();
		}
		fr(i,2,n){
			G[i]=read();
			sum[i]=(sum[i-1]+G[i])%mod;
		}
		while(lim<=n) lim<<=1;
		F[0]=(node){1,0};
		solve(0,lim-1);
		writeln((mod-F[n].y)*inv(F[n].x,mod)%mod);
		fr(i,2,n) G[i]=0;
		fr(i,0,lim-1) F[i]=(node){0,0};
	}
}