#include <bits/stdc++.h>
using namespace std;
struct Fast {Fast(){std::cin.tie(0);ios::sync_with_stdio(false);cout.precision(20);}} fast;

/* define */
#define FOR(I,X,Y) for(long long (I)=(X);(I)<(Y);(I)++)
#define REP(I,X,Y) for(long long (I)=(Y)-1;(I)>=(X);(I)--)
#define ALL(X) (X).begin(),(X).end()
#define pb push_back
#define COUNT(V,X) (upper_bound((V).begin(),(V).end(),X)-lower_bound((V).begin(),(V).end(),X))
#define debug(x) cerr<<#x<<':'<<x<<endl;
#define DEBUG(v) cerr<<#v<<':';for(auto xXx:v)cerr<<xXx<<' ';cerr<<endl;
#define Yes(X) if(X){cout<<"Yes"<<endl;}else{cout<<"No"<<endl;}
#define YES(X) if(X){cout<<"YES"<<endl;}else{cout<<"NO"<<endl;}
#define ctoi(C) (C-'0')

/* alias */
using ll = long long;
using ld = long double;
using vi = vector<int>;
using vii = vector<vector<int>>;
using vl = vector<long long>;
using vll = vector<vector<long long>>;
using pi = pair<int,int>;
using pl = pair<long long,long long>;
template<typename T> using PQ = priority_queue<T>;
template<typename T> using minPQ = priority_queue<T, vector<T>, greater<T>>;

/* const */
const long long dx[] = {1,0,-1,0};
const long long dy[] = {0,1,0,-1};
const long long dx8[] = {1,1,0,-1,-1,-1,0,1};
const long long dy8[] = {0,1,1,1,0,-1,-1,-1};
const long long dx9[] = {1,1,0,-1,-1,-1,0,1,0};
const long long dy9[] = {0,1,1,1,0,-1,-1,-1,0};
const int INF = 1000000007;
const long long LINF = 1000000000000000007;

/* func */
template <typename T> inline bool chmin(T& a, const T& b) {if (a > b) a = b; return a > b;}
template <typename T> inline bool chmax(T& a, const T& b) {if (a < b) a = b; return a < b;}
long long max(long long x,int y){return max(x,(long long)y);}
long long max(int x,long long y){return max((long long)x,y);}
long long min(long long x,int y){return min(x,(long long)y);}
long long min(int x,long long y){return min((long long)x,y);}

/* liblary */

struct Graph{
  long long V;
  long long E;
  //u,v,weight,cap
  vector<tuple<long long,long long,long long,long long>> edges;
  void add(long long u,long long v){edges.push_back(make_tuple(u,v,1,1));}
  void add(long long u,long long v,long long weight){edges.push_back(make_tuple(u,v,weight,1));}
  void add(long long u,long long v,long long weight,long long capacity){edges.push_back(make_tuple(u,v,weight,capacity));}
  Graph(long long V) : V(V){}
  Graph(long long V,long long E) : V(V),E(E){}
};

struct HLD{
    Graph G;
    ll root;
    vector<ll> DFS;
    vector<ll> subtree;
    vector<ll> pre;

    ll dfs(ll n,const vector<vector<pair<ll,ll>>> &adj){
        DFS[n] = 0;
        ll ans = 1;
        for(auto p:adj[n]){
            if(DFS[p.first] == -1){
                ans += dfs(p.first,adj);
                pre[p.first] = n;
            }
        }
        return DFS[n] = ans;
    }

    void HLdfs(ll n,ll r,const vector<vector<pair<ll,ll>>> &adj){
        subtree[n] = r;
        ll MAX = 0;
        bool flag = true;
        for(auto p:adj[n]){
            if(DFS[p.first] < DFS[n]){
                MAX = max(DFS[p.first],MAX);
            }
        }
        for(auto p:adj[n]){
            if(MAX == DFS[p.first] && flag){
                HLdfs(p.first,r,adj);
                flag = false;
            }
            else if(DFS[p.first] < DFS[n]){
                HLdfs(p.first,p.first,adj);
            }
        }
    }

    void depthdfs(ll n,ll pre,ll depth,const vector<vector<pair<ll,ll>>> &adj){
        DFS[n] = depth;
        for(auto p:adj[n]){
            if(p.first != pre){
                depthdfs(p.first,n,depth+p.second,adj);
            }
        }
    }

    ll lca(ll u,ll v){
        while(subtree[u] != subtree[v]){
            if(DFS[subtree[u]] < DFS[subtree[v]]){
                v = pre[subtree[v]];
            }
            else{
                u = pre[subtree[u]];
            }
        }
        return (DFS[u] < DFS[v] ? u : v);
    }

    ll dist(ll u,ll v){
        ll LCA = lca(u,v);
        return DFS[u]+DFS[v]-2*DFS[LCA];
    }

    HLD(Graph G,ll root = 0) : G(G),root(root) {
        vector<vector<pair<ll,ll>>> adj;
        adj.resize(G.V);
        DFS.resize(G.V);
        pre.resize(G.V);
        subtree.resize(G.V);
        fill(ALL(DFS),-1);
        for(auto t:G.edges)adj[get<0>(t)].push_back(make_pair(get<1>(t),get<2>(t)));
        dfs(root,adj);
        HLdfs(root,root,adj);
        depthdfs(root,root,1,adj);
    }
};

/* main */

signed main(){
    ll N;
    cin >> N;
    Graph G(N);
    G.E = N-1;
    FOR(i,0,N-1){
        ll a,b,c;
        cin >> a >> b >> c;
        a--;
        b--;
        G.add(a,b,c);
        G.add(b,a,c);
    }
    HLD hld(G);
    ll Q,K;
    cin >> Q >> K;
    K--;
    FOR(i,0,Q){
        ll x,y;
        cin >> x >> y;
        x--;
        y--;
        cout << hld.dist(x,K) + hld.dist(K,y) << endl;
    }
}

Measured memory_bytes: 37736