#include<bits/stdc++.h>
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
set<pair<pair<ll,ll>,ll> > s;
vector<pair<ll,ll> > vec[200020],qry[200020];
ll n,m,ans[200020];
struct BIT{
	ll tree[200020];
	il ll lowbit(ll x){
		return x&(-x);
	}
	il void mdf(ll x,ll v){
		while(x){
			tree[x]=(tree[x]+v)%mod;
			x-=lowbit(x);
		}
	}
	il ll query(ll x){
		ll res=0;
		while(x<=n){
			res=(res+tree[x])%mod;
			x+=lowbit(x);
		}
		return res;
	}
}T1,T2,T3,T4;
int main(){
	n=read();
	m=read();
	s.insert(MP(MP(-inf,inf),0));
	fr(i,1,n){
		ll l=read(),r=read();
		vec[i].push_back(MP(i,r-l));
		set<pair<pair<ll,ll>,ll> >::iterator it=--s.upper_bound(MP(MP(l+1,-inf),-inf));
		while(it!=s.end()){
			pair<pair<ll,ll>,ll> now=*it;
			if(now.fir.sec<=l){
				it++;
				continue;
			}
			if(now.fir.fir>=r) break;
			ll L=max(now.fir.fir,l),R=min(now.fir.sec,r);
			vec[i].push_back(MP(now.sec,(L-R+mod)%mod));
			s.erase(now);
			if(now.fir.fir<L) s.insert(MP(MP(now.fir.fir,L),now.sec));
			if(R<now.fir.sec) s.insert(MP(MP(R,now.fir.sec),now.sec));
			it=s.upper_bound(now);
		}
		s.insert(MP(MP(l,r),i));
	}
	fr(i,1,m){
		ll l=read(),r=read();
		qry[r].push_back(MP(l,i));
	}
	fr(i,1,n){
		fr(j,0,(ll)vec[i].size()-1){
			T1.mdf(vec[i][j].fir,(mod-vec[i][j].sec)%mod);
			T2.mdf(vec[i][j].fir,vec[i][j].sec*vec[i][j].fir%mod);
			T3.mdf(vec[i][j].fir,vec[i][j].sec*i%mod);
			T4.mdf(vec[i][j].fir,vec[i][j].sec*(mod-i)%mod*vec[i][j].fir%mod);
		}
		fr(j,0,(ll)qry[i].size()-1){
			ll l=qry[i][j].fir,len=i-l+1,res=0;
			res=(res+T1.query(l)*(i+1)%mod*(l-1))%mod;
			res=(res+T2.query(l)*(i+1))%mod;
			res=(res+T3.query(l)*(l-1))%mod;
			res=(res+T4.query(l))%mod;
			ans[qry[i][j].sec]=res*inv((len*(len+1)/2)%mod,mod)%mod;
		}
	}
	fr(i,1,m) writeln(ans[i]);
}
/*
2 1
1 5
4 8
1 2
ans:
5
*/