#include "bits/stdc++.h"
using namespace std;
#define int long long
#define all(x) begin(x), end(x)
#define sz(x) (int) (x).size()

const int mxn = 2e5+5;

int n;
vector<array<int,2>> adj[mxn];

//centroid
int vis[mxn], sub[mxn];
vector<array<int,2>> dist[mxn];

void dfs_dist(int v, int p, int dt, int o) {
	if (vis[v]) return;
	dist[o].push_back({v,dt});
	for (auto [u,d] : adj[v]) {
		if (u==p) continue;
		dfs_dist(u,v,dt+d,o);
	}
}
int dfs_sub(int v, int p) {
	if (vis[v]) return 0;
	sub[v] = 1;
	for (auto [u,d] : adj[v]) {
		if (u==p) continue;
		sub[v] += dfs_sub(u, v);
	}
	return sub[v];
}
int centroid(int v, int p, int sz) {
	for (auto [u,d] : adj[v]) {
		if (vis[u] || u==p) continue;
		if (sub[u]*2 > sz) return centroid(u, v, sz);
	}
	return v;
}
void build_centroid(int v) {
	int c = centroid(v,v,dfs_sub(v,v));
	dfs_dist(c, c, 0, c);
	vis[c] = 1;
	for (auto [u,d] : adj[c]) {
		if (vis[u]) continue;
		build_centroid(u);
	}
}

struct Tree {
	typedef int T;
	static constexpr T unit = 1e9;
	T f(T a, T b) { return min(a, b); } // (any associative fn)
	vector<T> s; int n;
	Tree(int n = 0, T def = unit) : s(2*n, def), n(n) {}
	void update(int pos, T val) {
		for (s[pos += n] = val; pos /= 2;)
			s[pos] = f(s[pos * 2], s[pos * 2 + 1]);
	}
	T query(int b, int e) { // query [b, e)
		T ra = unit, rb = unit;
		for (b += n, e += n; b < e; b /= 2, e /= 2) {
			if (b % 2) ra = f(ra, s[b++]);
			if (e % 2) rb = f(s[--e], rb);
		}
		return f(ra, rb);
	}
};

vector<array<int,3>> rg;
int q;
array<int,3> qry[5*mxn];
Tree rr;
int ans[mxn];

signed main() {
	ios::sync_with_stdio(false); cin.tie(nullptr);
		
	cin>>n;
	for (int i=1; i<n; i++) {
		int u,v,w; cin>>u>>v>>w; --u; --v;
		adj[u].push_back({v,w});
		adj[v].push_back({u,w});
	}
	
	build_centroid(0);
	
	for (int X=0; X<n; X++) {
		sort(all(dist[X]));
		stack<array<int,2>> mono;
		for (int i=0; i<sz(dist[X]); i++) {
			while (sz(mono) && mono.top()[1] > dist[X][i][1]) {mono.pop();}
			if (sz(mono)) {
				rg.push_back({mono.top()[0],dist[X][i][0],mono.top()[1]+dist[X][i][1]});
			}
			mono.push(dist[X][i]);
		}
		while (sz(mono)) mono.pop();
		for (int i=sz(dist[X])-1; i>=0; i--) {
			while (sz(mono) && mono.top()[1] > dist[X][i][1]) {mono.pop();}
			if (sz(mono)) {
				rg.push_back({dist[X][i][0],mono.top()[0],mono.top()[1]+dist[X][i][1]});
			}
			mono.push(dist[X][i]);
		}
	}
		
	rr = Tree(n+5);
	sort(all(rg)); reverse(all(rg));
	cin>>q;
	for (int i=0; i<q; i++) {
		cin>>qry[i][0]>>qry[i][1]; --qry[i][0], --qry[i][1];
		qry[i][2] = i;
	}
	sort(qry,qry+q);
	reverse(qry,qry+q);
	int rp = 0, qp = 0;
	if (n>10) cout<<q<<endl;
	for (int i=n-1; i>=0; i--) {
		while (rp < sz(rg) && rg[rp][0]==i) {
			int pp = rg[rp][1];
			int vv;
			vv = rr.query(pp,pp+1);
			rr.update(pp,min(vv,rg[rp][2]));
			rp++;
		}
		while (qp < q && qry[qp][0]==i) {
			ans[qry[qp][2]] = rr.query(i,qry[qp][1]+1);
			qp++;
		}
		if (qp < q && qry[qp][0]>n) {
			cout<<qry[qp][0]<<" "<<qry[qp][2]<<endl;
			cout<<qp<<endl;
			cout<<qry[qp+1][0]<<" "<<qry[qp+1][2]<<endl;
		}
	}
	if (qp != q) {
		cout<<qp<<"\n";
		cout<<qry[qp][0]<<" "<<qry[qp][1]<<endl;
		return 0;
	}
	for (int i=0; i<q; i++) {
		cout<<(ans[i]>1e15?-1:ans[i])<<"\n";
	}
	
	return 0;
}