#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, ll> pii;
int main() {
cin.tie(nullptr);
int n;
ll t;
cin >> n >> t;
vector<vector<pii>> ranges(n - 1);
for (int i = 0; i < n - 1; i++) {
int m;
cin >> m;
vector<pii> tmp(m);
for (auto& [A, B] : tmp)
cin >> A >> B;
sort(tmp.begin(), tmp.end(), [](const pii& x, const pii& y) {
if (x.second == y.second)
return x.first > y.first;
return x.second < y.second;
});
int mx = -1;
for (auto& [A, B] : tmp) {
if (A <= mx)
continue;
mx = A;
ranges[i].push_back({A, B});
}
reverse(ranges[i].begin(), ranges[i].end());
}
vector<int> dpthf, dpthr;
vector<pii> jmpf, jmpr, nxtf, nxtr;
vector<int> idxf, idxr;
vector<pii> prev;
vector<vector<int>> endf(n), endr(n);
for (int i = 1, cnt = 0; i < n; i++) {
vector<int> cidx, ends;
vector<pii> tmp;
for (int j = 0; j < ranges[i - 1].size(); j++) {
auto [A, B] = ranges[i - 1][j];
cidx.push_back(cnt);
idxf.push_back(i - 1);
nxtf.push_back({cnt, 0});
cnt++;
idxf.push_back(i);
nxtf.push_back({cnt - 1, B - A});
tmp.push_back({B, cnt});
ends.push_back(cnt);
cnt++;
}
endf[i] = ends;
if (!prev.empty()) {
bool cycled = false;
for (int j = 0, it = 0; j < ranges[i - 1].size(); j++) {
auto [A, B] = ranges[i - 1][j];
while (!cycled && prev[it].first > A) {
if (it == prev.size() - 1) {
it = 0;
cycled = true;
}
else
it++;
}
nxtf[cidx[j]] = {prev[it].second, (A - prev[it].first + t) % t};
}
}
prev = tmp;
}
prev.clear();
for (int i = n - 2, cnt = 0; i >= 0; i--) {
vector<int> cidx, ends;
vector<pii> tmp;
reverse(ranges[i].begin(), ranges[i].end());
for (int j = 0; j < ranges[i].size(); j++) {
auto [A, B] = ranges[i][j];
cidx.push_back(cnt);
idxr.push_back(i + 1);
nxtr.push_back({cnt, 0});
cnt++;
idxr.push_back(i);
nxtr.push_back({cnt - 1, B - A});
tmp.push_back({A, cnt});
ends.push_back(cnt);
cnt++;
}
endr[i] = ends;
if (!prev.empty()) {
bool cycled = false;
for (int j = 0, it = 0; j < ranges[i].size(); j++) {
auto [A, B] = ranges[i][j];
while (!cycled && prev[it].first < B) {
if (it == prev.size() - 1) {
it = 0;
cycled = true;
}
else
it++;
}
nxtr[cidx[j]] = {prev[it].second, (prev[it].first - B + t) % t};
}
}
prev = tmp;
}
jmpf.resize(idxf.size());
dpthf.resize(idxf.size(), 0);
for (int i = 0; i < idxf.size(); i++) {
auto [p, w] = nxtf[i];
if (p == i)
jmpf[i] = {i, 0};
else {
dpthf[i] = dpthf[p] + 1;
if (dpthf[jmpf[p].first] - dpthf[p] == dpthf[jmpf[jmpf[p].first].first] - dpthf[jmpf[p].first])
jmpf[i] = {jmpf[jmpf[p].first].first, jmpf[p].second + jmpf[jmpf[p].first].second + w};
else
jmpf[i] = {p, w};
}
}
jmpr.resize(idxr.size());
dpthr.resize(idxr.size(), 0);
for (int i = 0; i < idxr.size(); i++) {
auto [p, w] = nxtr[i];
if (p == i)
jmpr[i] = {i, 0};
else {
dpthr[i] = dpthr[p] + 1;
if (dpthr[jmpr[p].first] - dpthr[p] == dpthr[jmpr[jmpr[p].first].first] - dpthr[jmpr[p].first])
jmpr[i] = {jmpr[jmpr[p].first].first, jmpr[p].second + jmpr[jmpr[p].first].second + w};
else
jmpr[i] = {p, w};
}
}
int q;
cin >> q;
map<pii, ll> mp;
while (q--) {
int l, r;
cin >> l >> r;
l--, r--;
if (mp.count({l, r})) {
cout << mp[{l, r}] << '\n';
continue;
}
ll mina = LONG_MAX;
if (endr[l].size() > endf[r].size()) {
for (int v : endf[r]) {
ll sm = 0;
while (idxf[v] > l) {
if (idxf[jmpf[v].first] > l) {
sm += jmpf[v].second;
v = jmpf[v].first;
}
else {
sm += nxtf[v].second;
v = nxtf[v].first;
}
}
mina = min(mina, sm);
}
}
else {
for (int v : endr[l]) {
ll sm = 0;
while (idxr[v] < r) {
if (idxr[jmpr[v].first] < r) {
sm += jmpr[v].second;
v = jmpr[v].first;
}
else {
sm += nxtr[v].second;
v = nxtr[v].first;
}
}
mina = min(mina, sm);
}
}
mp[{l, r}] = mina;
cout << mina << '\n';
}
}
