#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define int ll
using pii = pair<int, int>;
#define fr first
#define sc second
pii join(pii a, pii b) {
return {a.fr + b.fr, b.sc};
}
int B = 400;
const int inf = 1e16;
signed main() {
int n, t;
cin >> n >> t;
vector<vector<pair<int, int>>> vec(n);
for (int i = 1; i <= n - 1; i ++) {
int m;
cin >> m;
for (int j = 1; j <= m; j ++) {
int a, b;
cin >> a >> b;
vec[i].push_back({a, b});
}
sort(vec[i].begin(), vec[i].end(), [&] (pii a, pii b) {return a.sc < b.sc;});
}
vector<vector<vector<pair<int, int>>>> lift(n);
for (int i = 1; i < n - 1; i ++) {
lift[i].resize(vec[i].size(), vector<pair<int, int>> (20));
int p = 0;
for (int j = 0; j < (int)vec[i].size(); j ++) {
while (p < (int)vec[i + 1].size() && vec[i + 1][p].fr < vec[i][j].sc)
p ++;
if (p < (int)vec[i + 1].size())
lift[i][j][0] = {vec[i + 1][p].fr - vec[i][j].fr, p};
else
lift[i][j][0] = {vec[i + 1][0].fr + t - vec[i][j].fr, 0};
}
}
for (int i = 1; i < 20; i ++) {
for (int j = 1; j < n - 1; j ++) {
for (int k = 0; k < (int)vec[j].size(); k ++) {
if (j + (1 << i) >= n)
continue;
lift[j][k][i] = join(lift[j][k][i - 1], lift[j + (1 << (i - 1))][lift[j][k][i - 1].sc][i - 1]);
}
}
}
auto time = [&] (int l, int k, int r) {
pii ans = {0, k};
for (int i = 19; i >= 0; i --) {
if (l + (1 << i) < r) {
ans = join(ans, lift[l][ans.sc][i]);
l += (1 << i);
}
}
return ans.fr + vec[r - 1][ans.sc].sc - vec[r - 1][ans.sc].fr;
};
int q;
cin >> q;
vector<int> ans(q, inf);
vector<vector<pii>> addQuery(n);
for (int i = 0; i < q; i ++) {
int l, r;
cin >> l >> r;
if ((int)vec[l].size() >= B) {
addQuery[l].push_back({r, i});
} else {
for (int j = 0; j < (int)vec[l].size(); j ++) {
ans[i] = min(ans[i], time(l, j, r));
}
}
}
for (int i = 1; i < n; i ++) {
if (addQuery[i].empty())
continue;
sort(addQuery[i].begin(), addQuery[i].end());
vector<int> vp;
int minn = inf;
for (int j = 0; j < (int)vec[i].size(); j ++) {
minn = min(minn, vec[i][j].sc - vec[i][j].fr);
vp.push_back(0);
}
int p = 0;
for (int j = i + 1; j <= n; j ++) {
while (p < (int)addQuery[i].size() && addQuery[i][p].fr == j) {
ans[addQuery[i][p].sc] = minn;
p ++;
}
if (j == n || p == (int)addQuery[i].size())
break;
minn = inf;
vector<int> vp2((int)vec[j].size(), inf);
for (int k = 0; k < (int)vec[j - 1].size(); k ++)
vp2[lift[j - 1][k][0].sc] = min(vp2[lift[j - 1][k][0].sc], vp[k] + lift[j - 1][k][0].fr);
for (int k = 0; k < (int)vec[j].size(); k ++)
minn = min(minn, vp2[k] + vec[j][k].sc - vec[j][k].fr);
vp = vp2;
}
}
for (int i = 0; i < q; i ++)
cout << ans[i] << '\n';
}
