#include<bits/stdc++.h>
using namespace std;
using ll=long long;
#ifdef sus
const int N=21, LG=5, S=4;
#else
const int N=1e5+10, LG=17, S=700;
#endif
int rjump[LG][N], pos[N], lcost[LG][N];
ll rcost[LG][N], ljump[LG][N];
int jump[N/S+10][N];
ll cost[N/S+10][N], mem[N][N/S+10];
int nxt[N];
vector<pair<int, int>> v;
int n, t, q;
vector<pair<int, int>> edge[N];
ll get_rcost(int l, int r, int idl){
int d=r-l;
int cur=idl;
ll ans=0;
for (int k=0; k<LG; ++k) if (d>>k&1){
ans+=rcost[k][cur];
cur=rjump[k][cur];
}
int j=v[cur].second;
return ans+edge[r][j].second-edge[r][j].first;
}
ll get_lcost(int l, int r, int idr){
int d=r-l;
int cur=idr;
ll ans=0;
for (int k=0; k<LG; ++k) if (d>>k&1){
ans+=lcost[k][cur];
cur=ljump[k][cur];
}
int j=v[cur].second;
return ans+edge[l][j].second-edge[l][j].first;
}
ll get_cost(int l, int r, int idl){
int d=r-l;
int cur=jump[d][idl];
int j=v[cur].second;
return cost[d][idl]+edge[r][j].second-edge[r][j].first;
}
int32_t main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cin >> n >> t;
for (int i=1; i<n; ++i){
int m; cin >> m;
vector<pair<int, int>> tmp(m);
for (auto &j:tmp) cin >> j.first >> j.second;
sort(tmp.begin(), tmp.end(), [&](pair<int, int> x, pair<int, int> y){
return make_pair(x.first, -x.second)<make_pair(y.first, -y.second);
});
for (auto &j:tmp){
while (edge[i].size() && edge[i].back().second>=j.second) edge[i].pop_back();
edge[i].push_back(j);
}
pos[i]=v.size();
for (int j=0; j<(int)edge[i].size(); ++j) v.emplace_back(i, j);
}
for (int id=0; id<(int)v.size(); ++id){
jump[0][id]=id;
cost[0][id]=0;
}
for (int id=0; id<(int)v.size(); ++id){
int i=v[id].first, j=v[id].second;
if (i==n-1) break;
int i2=i+1;
int j2=lower_bound(edge[i2].begin(), edge[i2].end(), make_pair(edge[i][j].second, -1))-edge[i2].begin();
j2%=(int)edge[i2].size();
rcost[0][id]=edge[i2][j2].first>=edge[i][j].second?edge[i2][j2].first-edge[i][j].first:edge[i2][j2].first-edge[i][j].first+t;
rjump[0][id]=pos[i2]+j2;
jump[1][id]=rjump[0][id];
cost[1][id]=rcost[0][id];
}
for (int k=2; k<N/S+10; ++k){
for (int id=0; id<(int)v.size(); ++id){
if (v[id].first+k>n-1) break;
jump[k][id]=jump[1][jump[k-1][id]];
cost[k][id]=cost[k-1][id]+cost[1][jump[k-1][id]];
}
}
for (int k=1; k<LG; ++k){
for (int id=0; id<(int)v.size(); ++id){
if (v[id].first+(1<<k)>n-1) break;
rjump[k][id]=rjump[k-1][rjump[k-1][id]];
rcost[k][id]=rcost[k-1][id]+rcost[k-1][rjump[k-1][id]];
}
}
for (int id=(int)v.size()-1; id>=0; --id){
int i=v[id].first, j=v[id].second;
if (i==1) break;
int i2=i-1;
int j2=lower_bound(edge[i2].begin(), edge[i2].end(), make_pair(-1, edge[i][j].first+1), [&](pair<int, int> x, pair<int, int> y){
return make_pair(x.second, x.first)<make_pair(y.second, y.first);
})-edge[i2].begin();
j2=(j2+(int)edge[i2].size()-1)%(int)edge[i2].size();
lcost[0][id]=edge[i2][j2].second<=edge[i][j].first?edge[i][j].second-edge[i2][j2].second:edge[i][j].second-edge[i2][j2].second+t;
ljump[0][id]=pos[i2]+j2;
}
for (int k=1; k<LG; ++k){
for (int id=(int)v.size()-1; id>=0; --id){
if (v[id].first-(1<<k)<1) break;
ljump[k][id]=ljump[k-1][ljump[k-1][id]];
lcost[k][id]=lcost[k-1][id]+lcost[k-1][ljump[k-1][id]];
}
}
nxt[n]=n;
for (int i=n-1; i>=1; --i){
if ((int)edge[i].size()<S) nxt[i]=i;
else nxt[i]=nxt[i+1];
}
memset(mem, -1, sizeof mem);
cin >> q;
while (q--){
int l, r; cin >> l >> r;
--r;
ll ans=1e18;
if (nxt[l]<=r){
int i=nxt[l];
for (int j=pos[i]; j<pos[i]+(int)edge[i].size(); ++j) ans=min(ans, get_lcost(l, i, j)+get_rcost(i, r, j)-edge[i][j-pos[i]].second+edge[i][j-pos[i]].first);
}else{
int d=r-l;
if (mem[l][d]!=-1) ans=mem[l][d];
else{
for (int i=pos[l]; i<pos[l]+(int)edge[l].size(); ++i) ans=min(ans, get_cost(l, r, i));
mem[l][d]=ans;
}
}
cout << ans << '\n';
}
return 0;
}
