#include <bits/stdc++.h>
using namespace std;
#define modulo 1000000007
#define mod(mod_x) ((((long long)mod_x+modulo))%modulo)
#define Inf 2000000000000000000
vector<vector<pair<long long,int>>> e;

struct Tree{
	int G;
	vector<int> L;
	vector<int> number;
	vector<Tree> Ts;
	vector<vector<pair<long long,int>>> E;
	vector<long long> mini;
	vector<int> P;
	Tree(){
	}
	Tree(vector<vector<pair<long long,int>>> EE){
		
		
		
		E = EE;
		vector<int> sz(E.size(),0);
		dfs(E,sz,0,-1);
		//cout<<G<<endl;
		P.resize(E.size(),-1);
		L.resize(E.size(),-1);
		mini.resize(E.size(),Inf);
		for(int i=0;i<E[G].size();i++){
			if(E[G][i].second!=-1)dfs2(E,E[G][i].second,G,i,Inf);
		}

		number.resize(E.size(),0);
		vector<int> t(E[G].size(),0);
		for(int i=0;i<E.size();i++){
			if(L[i]==-1)continue;
			number[i] = t[L[i]];
			t[L[i]]++;
		}

		
		vector<vector<vector<pair<long long,int>>>> nE(E[G].size());
		for(int i=0;i<t.size();i++){
			nE[i].resize(t[i],vector<pair<long long,int>>());
		}
		
		for(int i=0;i<E.size();i++){
			if(i==G)continue;
			for(int j=0;j<E[i].size();j++){
				int to  =E[i][j].second;
				if(to!=-1&&L[to]!=-1&&L[i]==L[to]){
					//cout<<i<<','<<to<<endl;
					nE[L[i]][number[i]].emplace_back(E[i][j].first,number[to]);
				}
				else if(j<3){
					//cout<<i<<','<<to<<endl;
					nE[L[i]][number[i]].emplace_back(E[i][j].first,-1);
				}
			}
		}
		if(E.size()>2){
			Ts.resize(E[G].size());
			
			for(int i=0;i<E[G].size();i++){
				if(E[G][i].second==-1)continue;
				Ts[i] = Tree(nE[i]);
			}
		}
	}
	
	void dfs(auto &E,auto &sz,int now,int p){
		sz[now] = 1;
		bool f = true;
		for(int i=0;i<E[now].size();i++){
			int to = E[now][i].second;
			if(to==-1)continue;
			if(to==p)continue;
			dfs(E,sz,to,now);
			sz[now] += sz[to];
			if(sz[to]*2>E.size())f=false;
		}
		if((E.size()-sz[now])*2>E.size())f=false;
		if(f)G = now;
	}
	
	void dfs2(auto &E,int now,int p,int l,long long M){
		mini[now] = M;
		P[now] = p;
		multiset<pair<long long,int>> S;
		for(int i=0;i<E[now].size();i++){
			int to = E[now][i].second;
			if(to==p)continue;
			S.insert(E[now][i]);
		}
		L[now] = l;
		for(int i=0;i<E[now].size();i++){
			int to = E[now][i].second;
			if(to==-1)continue;
			if(to==p)continue;
			long long t = Inf;
			auto it = S.begin();

			if(it->second==to)it++;
			if(it!=S.end()){
				t = it->first;
			}
			dfs2(E,to,now,l,min(M,t));
		}
	}
	
	long long get(int u,int v){

		if(u!=G&&v!=G&&L[u]==L[v]){
			return Ts[L[u]].get(number[u],number[v]);
		}
		if(v==G)swap(u,v);
		long long ret = Inf;
		if(u!=G){
			for(int i=0;i<E[u].size();i++){
				if(i==3)break;
				int to = E[u][i].second;
				if(to==P[u])continue;
				ret = min(ret,E[u][i].first);
			}
			for(int i=0;i<E[v].size();i++){
				if(i==3)break;
				int to = E[v][i].second;
				if(to==P[v])continue;
				ret = min(ret,E[v][i].first);
			}
			ret = min(ret,mini[u]);
			ret = min(ret,mini[v]);
			
		}
		else{
			
			for(int i=0;i<E[u].size();i++){
				if(i==3)break;
				int to = E[u][i].second;
				if(to==-1)continue;
				if(L[v]==L[to])continue;
				ret = min(ret,E[u][i].first);
			}
			for(int i=0;i<E[v].size();i++){
				if(i==3)break;
				int to = E[v][i].second;
				if(to==P[v])continue;
				ret = min(ret,E[v][i].first);
			}
			ret = min(ret,mini[v]);
		}

		for(int i=0;i<E[G].size();i++){
			if(i==3)break;
			int to = E[G][i].second;
			if(to!=-1){
				if(L[u]==L[to]||L[v]==L[to])continue;
			}
			ret = min(ret,E[G][i].first);
		}
		return ret;
	}
	
};

struct lca{
	
	vector<int> depth;//depth[i] 頂点iの深さ
	vector<vector<int>> parents;//parents[i][j] 頂点iから2^j個上の親
	
	int max_j = 30;
	
	lca(int n,vector<vector<int>> &E){
		depth.assign(E.size(),-1);
		parents.assign(E.size(),vector<int>(max_j,-1));
		
		stack<int> s;
		s.push(n);
		depth[n] = 0;
		while(s.size()!=0){
			int k = s.top();
			s.pop();
			for(int i=0;i<E[k].size();i++){
				int x = E[k][i];
				if(depth[x]!=-1)continue;
				s.push(x);
				depth[x] = depth[k]+1;
				for(int j=0;j<max_j;j++){
					if(j==0){
						parents[x][j] = k;
					}
					else{
						parents[x][j] = parents[parents[x][j-1]][j-1];
					}
					if(parents[x][j] == -1)break;
				}
			}
		}
	}
	
	//頂点uのk番目の親
	int kth_parent(int u,int k){
		for(int i=0;i<max_j;i++){
			if(k==0)break;
			if(u==-1)break;
			if(k%2){
				u = parents[u][i];
			}
			k/=2;
		}
		return u;
	}
	
	int query(int u,int v){
		if(depth[u]<depth[v])swap(u,v);
		u = kth_parent(u,depth[u]-depth[v]);
		
		if(u==v){
			return u;
		}
		
		for(int i=max_j-1;i>=0;i--){
			if(parents[u][i]!=parents[v][i]){
				u = parents[u][i];
				v = parents[v][i];
			}
		}
		
		return parents[u][0];
		
	}
	
	int get_distance(int u,int v){
		return depth[u]+depth[v]-2*depth[query(u,v)];
	}
	
	
};

vector<long long> dis;
void dfs(auto &E,int now,int p){
	for(int i=0;i<E[now].size();i++){
		int to = E[now][i].second;
		if(to==p)continue;
		dis[to] = dis[now] + E[now][i].first;
		dfs(E,to,now);
	}
}

int main(){
	
	int N;
	cin>>N;
	
	e.resize(N,vector<pair<long long,int>>());
	vector<vector<int>> ee(N,vector<int>());
	for(int i=0;i<N-1;i++){
		int u,v,w;
		cin>>u>>v>>w;
		u--;v--;
		e[u].emplace_back(w,v);
		e[v].emplace_back(w,u);
		ee[u].push_back(v);
		ee[v].push_back(u);
	}
	
	
	for(int i=0;i<N;i++){
		sort(e[i].begin(),e[i].end());
	}
	dis.resize(N,0LL);
	dfs(e,0,-1);
	Tree T(e);
	
	lca L(0,ee);
	int Q;
	cin>>Q;
	for(int i=0;i<Q;i++){
		int x,y;
		scanf("%d %d",&x,&y);
		x--;y--;
		long long z = T.get(x,y);
		//cout<<z<<endl;
		if(z==Inf)cout<<-1<<endl;
		else{
			long long ans = dis[x] + dis[y] - dis[L.query(x,y)]*2 + z*2;
			cout<<ans<<endl;
		}
	}
	
	
	return 0;
}