#include <iostream>
#include <algorithm>
#include <vector>

typedef long long ll;
typedef double lf;

// #define DEBUG 1
struct IO
{
    #define MAXSIZE (1 << 20)
    #define isdigit(x) (x >= '0' && x <= '9')
    char buf[MAXSIZE], *p1, *p2;
    char pbuf[MAXSIZE], *pp;
    #if DEBUG
    #else
    IO() : p1(buf), p2(buf), pp(pbuf) {}
    ~IO() {fwrite(pbuf, 1, pp - pbuf, stdout);}
    #endif
    #define gc() (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, MAXSIZE, stdin), p1 == p2) ? ' ' : *p1++)
    #define blank(x) (x == ' ' || x == '\n' || x == '\r' || x == '\t')

    template <typename T>
    void Read(T &x)
    {
        #if DEBUG
        std::cin >> x;
        #else
        bool sign = 0; char ch = gc(); x = 0;
        for (; !isdigit(ch); ch = gc())
            if (ch == '-') sign = 1;
        for (; isdigit(ch); ch = gc()) x = x * 10 + (ch ^ 48);
        if (sign) x = -x;
        #endif
    }
    void Read(char *s)
    {
        #if DEBUG
        std::cin >> s;
        #else
        char ch = gc();
        for (; blank(ch); ch = gc());
        for (; !blank(ch); ch = gc()) *s++ = ch;
        *s = 0;
        #endif
    }
    void Read(char &c) {for (c = gc(); blank(c); c = gc());}

    void Push(const char &c)
    {
        #if DEBUG
        putchar(c);
        #else
        if (pp - pbuf == MAXSIZE) fwrite(pbuf, 1, MAXSIZE, stdout), pp = pbuf;
        *pp++ = c;
        #endif
    }
    template <typename T>
    void Write(T x)
    {
        if (x < 0) x = -x, Push('-');
        static T sta[35];
        int top = 0;
        do sta[top++] = x % 10, x /= 10; while (x);
        while (top) Push(sta[--top] ^ 48);
    }
    template <typename T>
    void Write(T x, char lst) {Write(x), Push(lst);}
} IO;
#define Read(x) IO.Read(x)
#define Write(x, y) IO.Write(x, y)
#define Put(x) IO.Push(x)

using namespace std;

const int MAXN = 1e5 + 10, MAXM = 3e5 + 10;

int n, T, q;

struct line
{
    int x, y, l;
    bool operator < (const line &u) const { return y == u.y ? x > u.x : y < u.y; }
}pl[MAXN], b[MAXN];
int m[MAXN], top;
line *a[MAXN];

struct Qry
{
    int l, r; ll res;
}qt[MAXN];
vector <int> vt[MAXN], vtb[MAXN];

int val[MAXN], fa[MAXN], lay[MAXN];
vector <pair <int, int>> e[MAXN];
ll dep[MAXN];
inline void DFS1(int u)
{
    dep[u] += val[u];
    for (auto [v, w] : e[u])
        dep[v] = dep[u] + w, DFS1(v);
}

ll mns, rval[MAXN];
inline void DFS2(int u)
{
    rval[lay[u]] = min(rval[lay[u]], dep[u] - mns);
    for (auto [v, w] : e[u]) DFS2(v);
}

ll tr[MAXN * 20]; int ls[MAXN * 20], rs[MAXN * 20];
int rt[MAXN], tot;
inline void Pushup(int cur) { tr[cur] = min(tr[ls[cur]], tr[rs[cur]]); }
void Update(int &cur, int l, int r, int x, ll k)
{
    if (!cur) cur = ++tot, tr[cur] = 1e18;
    if (l == r) tr[cur] = k;
    else
    {
        int mid = l + r >> 1;
        if (x <= mid) Update(ls[cur], l, mid, x, k);
        else Update(rs[cur], mid + 1, r, x, k);
        Pushup(cur);
    }
}
int Merge(int u, int v, int l, int r)
{
    if (!u || !v) return u | v;
    if (l == r) return tr[u] = min(tr[u], tr[v]), u;
    int mid = l + r >> 1;
    ls[u] = Merge(ls[u], ls[v], l, mid), rs[u] = Merge(rs[u], rs[v], mid + 1, r);
    Pushup(u);
    return u;
}
ll Query(int cur, int l, int r, int x)
{
    if (!cur) return 1e18;
    if (l == r) return tr[cur];
    int mid = l + r >> 1;
    if (x <= mid) return Query(ls[cur], l, mid, x);
    return Query(rs[cur], mid + 1, r, x);
}

inline void DFS3(int u)
{
    Update(rt[u], 1, n, lay[u], dep[u]);
    for (auto [v, w] : e[u])
        DFS3(v), Merge(rt[u], rt[v], 1, n);
    for (auto x : vt[u])
        qt[x].res = min(qt[x].res, Query(rt[u], 1, n, qt[x].l) - dep[u] + val[u]);
}

int main()
{
    // freopen("A.in", "r", stdin);
    // freopen("A.out", "w", stdout);
    #if DEBUG
    #else
    ios::sync_with_stdio(0), cin.tie(0);
    #endif
    Read(n), Read(T);
    for (int i = 1; i < n; i++)
    {
        Read(m[i]), a[i] = pl + top;
        for (int j = 1; j <= m[i]; j++) Read(b[j].x), Read(b[j].y), b[j].l = i;
        sort(b + 1, b + m[i] + 1);
        for (int i = 1; i <= m[i]; i++)
            if (i == 1 || b[i].x > b[i - 1].x) pl[++top] = b[i];
        m[i] = pl + top - a[i];
    }
    for (int i = 1; i < n - 1; i++)
    {
        int cur = a[i] - pl + 1;
        for (int j = 1, k = 1; j <= m[i]; j++, cur++)
        {
            while (k <= m[i + 1] && a[i + 1][k].x < a[i][j].y) k++;
            if (k > m[i + 1])
            {
                fa[cur] = a[i + 1] + 1 - pl;
                e[fa[cur]].emplace_back(cur, pl[fa[cur]].x - pl[cur].y + T);
            }
            else
            {
                fa[cur] = a[i + 1] + k - pl;
                e[fa[cur]].emplace_back(cur, pl[fa[cur]].x - pl[cur].y);
            }
            val[cur] = a[i][j].y - a[i][j].x, lay[cur] = i;
        }
    }
    for (int i = 1, cur = a[n - 1] - pl + 1; i <= m[n - 1]; i++, cur++)
        val[cur] = a[n - 1][i].y - a[n - 1][i].x, fa[cur] = 0, lay[cur] = n - 1, e[0].emplace_back(cur, 0);
    DFS1(0);

    int B = 50;
    Read(q);
    for (int i = 1; i <= q; i++)
    {
        Read(qt[i].l), Read(qt[i].r);
        if (qt[i].l == qt[i].r) qt[i].res = 0;
        else if (m[qt[i].r - 1] <= B)
        {
            qt[i].res = 2e9;
            for (int j = 1; j <= m[qt[i].r - 1]; j++)
                vt[a[qt[i].r - 1] + j - pl].push_back(i);
        }
        else vtb[qt[i].r - 1].push_back(i);
    }
    for (int i = 1; i <= n; i++)
        if (m[i] > B && vtb[i].size())
        {
            for (int j = 1; j <= i; j++) rval[j] = 1e18;
            for (int j = 1; j <= m[i]; j++)
                mns = dep[a[i] + j - pl] - val[a[i] + j - pl], DFS2(a[i] + j - pl);
            for (auto x : vtb[i])
                qt[x].res = rval[qt[x].l];
        }
    DFS3(0);
    for (int i = 1; i <= q; i++) cout << qt[i].res << '\n';
    return 0;
}