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#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;

#define fi first
#define se second
#define pp push_back
#define all(x) (x).begin(), (x).end()
#define Ones(n) __builtin_popcount(n)
#define endl '\n'
#define mem(arrr, xx) memset(arrr,xx,sizeof arrr)
//#define int long long
#define debug(x) cout << (#x) << " = " << x << endl

void Gamal() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
#ifdef Clion
    freopen("input.txt", "r", stdin), freopen("output.txt", "w", stdout);
#endif
}

int dx[] = {+0, +0, -1, +1, +1, +1, -1, -1};
int dy[] = {-1, +1, +0, +0, +1, -1, +1, -1};

const double EPS = 1e-9;
const ll OO = 0X3F3F3F3F3F3F3F3F;
const int N = 1e5 + 5, INF = INT_MAX, MOD = 1e9 + 7, LOG = 20;

struct SEG {
    ll sum = 0;

    SEG() {
    }

    SEG(ll x) {
        sum = x;
    }
};

struct segTree {
    vector<SEG> seg;
    int sz = 1, n;

    segTree(int nn) {
        n = nn;
        while (sz < nn)
            sz *= 2;
        seg.assign(2 * sz, SEG());
    }

    SEG merge(SEG seg1, SEG seg2) {
        SEG ret;
        ret.sum = max(seg1.sum, seg2.sum);
        return ret;
    }


    void update(int i, ll val, int x, int lx, int rx) {
        if (lx == rx) {
            seg[x] = SEG(val);
            return;
        }
        int mid = (lx + rx) / 2, lf = 2 * x + 1, rt = 2 * x + 2;
        if (i <= mid)
            update(i, val, lf, lx, mid);
        else
            update(i, val, rt, mid + 1, rx);
        seg[x] = merge(seg[lf], seg[rt]);
    }

    void update(int i, ll val) {
        update(i, val, 0, 0, n - 1);
    }

    SEG query(int l, int r, int x, int lx, int rx) {
        if (l <= lx && r >= rx)
            return seg[x];
        if (l > rx || r < lx)
            return {};

        int mid = (lx + rx) / 2, lf = 2 * x + 1, rt = 2 * x + 2;

        return merge(query(l, r, lf, lx, mid), query(l, r, rt, mid + 1, rx));
    }

    SEG query(int l, int r) {
        return query(l, r, 0, 0, n - 1);
    }
};

vector<pii> adj[N];
vector<int> at[N];
ll sum[N];
int in[N], out[N], depth[N], timer;

void dfs(int u, int p) {
    in[u] = timer++;
    at[depth[u]].push_back(u);
    for (auto &[v, w]: adj[u]) {
        if (v == p)continue;
        sum[v] = sum[u] + w;
        depth[v] = depth[u] + 1;
        dfs(v, u);
    }
    out[u] = timer - 1;
}

void solve() {
    int n;
    cin >> n;
    for (int i = 0; i < n - 1; ++i) {
        int u, v, w;
        cin >> u >> v >> w;
        adj[u].emplace_back(v, w);
        adj[v].emplace_back(u, w);
    }
    int q;
    cin >> q;
    vector<pll> que(q);
    vector<int> L(q, 0), R(q, n - 1), ans(q, -1);
    for (int i = 0; i < q; ++i) {
        int u;
        cin >> u;
        ll p;
        cin >> p;
        que[i] = {u, p};
    }
    dfs(1, 1);
    bool ok = true;
    while (ok) {
        vector<int> ev[n];
        segTree seg(n);
        ok = false;
        for (int i = 0; i < q; ++i) {
            if (L[i] > R[i])continue;
            int mid = (L[i] + R[i]) / 2;
            ev[mid].push_back(i);
            ok = true;
        }
        for (int i = 0; i < n; ++i) {
            for (auto &u: at[i]) {
                seg.update(in[u], sum[u]);
            }
            for (auto &j: ev[i]) {
                ll val = seg.query(in[que[j].first], out[que[j].first]).sum - sum[que[j].first];
                if (val >= que[j].second) {
                    ans[j] = i;
                    R[j] = i - 1;
                } else {
                    L[j] = i + 1;
                }
            }
        }
    }
    for (int i = 0; i < q; ++i) {
        if (ans[i] == -1)cout << -1 << endl;
        else cout << ans[i] - depth[que[i].first] << endl;
    }
}


signed main() {
    Gamal();
    int t = 1;
//    cin >> t;
    while (t--) {
        solve();
    }
}