#include<bits/stdc++.h>
#define Gc() getchar()
#define Me(x,y) memset(x,y,sizeof(x))
#define Mc(x,y) memcpy(x,y,sizeof(x))
#define d(x,y) ((m)*(x-1)+(y))
#define R(n) (rnd()%(n)+1)
#define Pc(x) putchar(x)
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define eb emplace_back
#define all(x) x.begin(),x.end()
using namespace std;using ll=long long;using db=double;using lb=long db;using ui=unsigned;using ull=unsigned long long;using pii=pair<int,int>;
const int N=2.5e5+5,M=N*4+5,K=1000+5,mod=1e9+7,Mod=mod-1;const db eps=1e-9;const int INF=1e9+7;mt19937 rnd(28382);
#define Tp template<typename T>
#define Ts template<typename T,typename... Ar>
namespace Debug{
	Tp void _debug(char* f,T t){cerr<<f<<'='<<t<<endl;}
	Ts void _debug(char* f,T x,Ar... y){while(*f!=',') cerr<<*f++;cerr<<'='<<x<<",";_debug(f+1,y...);}
	#ifdef LOCAL
	#define gdb(...) _debug((char*)#__VA_ARGS__,__VA_ARGS__)
	#else 
	#define gdb(...) void()
	#endif
}using namespace Debug;
int n,T,m,A[N],B[N],fa[N],w[N];
int bg[N],en[N];
int t1[N][350];ll w1[N][350];
int t2[N][350];ll w2[N][350];
const int k=320;
int pre[N];
void Solve(){
	scanf("%d%d",&n,&T);
	int La=1;
	for(int i=1;i<n;i++){
		bg[i]=m+1;
		int len;scanf("%d",&len);
		vector<pii> C(len);
		for(int j=0;j<len;j++) scanf("%d%d",&C[j].fi,&C[j].se);
		sort(all(C));
		for(auto [a,b]:C){
			while(m>=bg[i]&&B[m]>=b) m--;
			A[++m]=a;B[m]=b;
		}
		en[i]=m;
	}
	for(int i=2;i<n;i++){
		int R=bg[i];
		for(int j=bg[i-1];j<=en[i-1];j++){
			while(R<=en[i]&&A[R]<B[j]) R++;
			if(R>en[i]) fa[j]=bg[i],w[j]=T-B[j]+B[fa[j]];
			else fa[j]=R,w[j]=B[R]-B[j];
		}
	}
	for(int i=m;i;i--){
		t1[i][0]=t2[i][0]=i;w1[i][0]=w2[i][0]=0;
		for(int j=1;j<=k;j++) t1[i][j]=t1[fa[i]][j-1],w1[i][j]=w[i]+w1[fa[i]][j-1];
		for(int j=1;j<=k;j++) t2[i][j]=t2[t1[i][k]][j-1],w2[i][j]=w1[i][k]+w2[t1[i][k]][j-1];
	}
	for(int i=1;i<=n;i++){
		for(int j=bg[i]+1;j<=en[i];j++) pre[j]=(t1[j][k]^t1[j-1][k]?j-1:pre[j-1]);
	}
	map<pii,ll> f;
	int q;scanf("%d",&q);
	auto calc=[](int x,int y){
		return w2[x][y/k]+w1[t2[x][y/k]][y%k];
	};
	while(q--){
		int x,y;scanf("%d%d",&x,&y);
		if(auto it=f.find(make_pair(x,y));it!=f.end()){printf("%lld\n",it->se);continue;}
		ll ans=1e18;
		for(int i=en[x];i>=bg[x];y-x-1>k?i=pre[i]:i--) ans=min(ans,calc(i,y-x-1)+B[i]-A[i]);
		printf("%lld\n",f[make_pair(x,y)]=ans);
	}
}
int main(){
	int t=1;
	// scanf("%d",&t);
	while(t--) Solve();
	cerr<<clock()*1.0/CLOCKS_PER_SEC<<'\n';
}