//----------vahagng----------//
#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
using namespace std;
// using namespace __gnu_pbds;
// template <class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
void print(long long t) { cerr << t; }
void print(int t) { cerr << t; }
void print(string t) { cerr << t; }
void print(char t) { cerr << t; }
void print(double t) { cerr << t; }
void print(long double t) { cerr << t; }
void print(unsigned long long t) { cerr << t; }
template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(T v[], V n) { cerr << "["; for (int i = 0; i < n; i++) { cerr << v[i] << " "; } cerr << "]"; }
template <class T, class V> void print(pair <T, V> p) { cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}"; }
template <class T> void print(vector <T> v) { cerr << "[ "; for (T i : v) { print(i); cerr << " "; } cerr << "]"; }
template <class T> void print(set <T> v) { cerr << "[ "; for (T i : v) { print(i); cerr << " "; } cerr << "]"; }
template <class T> void print(unordered_set <T> v) { cerr << "[ "; for (T i : v) { print(i); cerr << " "; } cerr << "]"; }
template <class T> void print(multiset <T> v) { cerr << "[ "; for (T i : v) { print(i); cerr << " "; } cerr << "]"; }
template <class T, class V> void print(map <T, V> v) { cerr << "[ "; for (auto i : v) { print(i); cerr << " "; } cerr << "]"; }
#define ll long long
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define ld long double
#define sz(v) v.size()
#define endl '\n'
#define stress_test freopen("out.txt", "r", stdin); freopen("in.txt", "w", stdout);
const ll inf = 8e18, mod = 1e9 + 7, mod2 = 998244353;
void SetIO(string str = "") {
if (str != "") {
freopen((str + ".in").c_str(), "r", stdin);
freopen((str + ".out").c_str(), "w", stdout);
}
else {
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
}
}
void FastIO() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
}
// mt19937 rnd(chrono::system_clock::now().time_since_epoch().count());
const int N = 1e5 + 10, sq = 500, M = 2e5 + 10, Q = pow(3, 7);
int n, s, q, e, tin[N], tout[N], timer, par[N];
ll dist[N], id[N], ans[N], answ[N];
vector<pair<ll, ll>> adj[N], edges;
bool marked[N];
// answ[i] = 1 -> escaped
// answ[i] = 0 -> oo
// answ[i] = -1 -> xanut
void dfs(int node, int parent){
tin[node] = ++timer;
id[tin[node]] = node;
par[node] = parent;
for(auto [u, w] : adj[node]){
if(u == parent) continue;
dist[u] = dist[node] + w;
dfs(u, node);
}
tout[node] = timer;
}
bool herna(int u, int v){
return tin[v] >= tin[u] && tout[v] <= tout[u];
}
struct segtree{
struct Node{
__int128_t mn, lazy;
};
int size = 1;
vector<Node> stree;
void init(){
while(size <= n) size <<= 1;
stree.assign(4*size, {(__int128_t)50 * inf, 0});
build(0, 0, size);
}
void build(int x, int lx, int rx){
if(rx - lx == 1){
if(1 <= lx && lx <= n && marked[lx]){
stree[x].mn = dist[id[lx]];
}
return;
}
int m =(lx + rx) / 2;
build(2*x+1, lx, m);
build(2*x+2, m, rx);
stree[x].mn = min(stree[2*x+1].mn, stree[2*x+2].mn);
}
void push(int x, int lx, int rx){
if(rx - lx == 1) return;
stree[2*x+1].lazy += stree[x].lazy;
stree[2*x+2].lazy += stree[x].lazy;
stree[2*x+1].mn += stree[x].lazy;
stree[2*x+2].mn += stree[x].lazy;
stree[x].lazy = 0;
}
void upd(int l, int r, ll v, int x, int lx, int rx){
push(x, lx, rx);
if(lx >= r || rx <= l) return;
if(lx >= l && rx <= r){
stree[x].mn += v;
stree[x].lazy += v;
return;
}
int m = (lx + rx) / 2;
upd(l, r, v, 2*x+1, lx, m);
upd(l, r, v, 2*x+2, m, rx);
stree[x].mn = min(stree[2*x+1].mn, stree[2*x+2].mn);
}
__int128_t qry(int l, int r, int x, int lx, int rx){
push(x, lx, rx);
if(lx >= r || rx <= l) return (__int128_t)50 * inf;
if(lx >= l && rx <= r) return stree[x].mn;
int m = (lx + rx) / 2;
return min(qry(l, r, 2*x+1, lx, m), qry(l, r, 2*x+2, m, rx));
}
void upd(int l, int r, ll v){
upd(l, r, v, 0, 0, size);
}
__int128_t qry(int l, int r){
return qry(l, r, 0, 0, size);
}
}st;
struct QRY{
int R, ind;
};
vector<QRY> qrs[N];
void reroot(int node, int parent){
for(auto [R, ind] : qrs[node]){
auto [u, v] = edges[R];
if(par[v] == u) swap(u, v);
if(herna(u, node)){
if(herna(u, e)){
answ[ind] = 1;
}else{
// xanut u-i subum
__int128_t qr = st.qry(tin[u], tout[u] + 1);
if(qr >= (__int128_t)40 * inf){
answ[ind] = 0;
}else{
answ[ind] = -1;
ans[ind] = qr;
}
}
}else{
if(herna(u, e)){
__int128_t qr = min(st.qry(1, tin[u]), st.qry(tout[u] + 1, n + 1));
if(qr >= (__int128_t)40 * inf){
answ[ind] = 0;
}else{
answ[ind] = -1;
ans[ind] = qr;
}
}else{
answ[ind] = 1;
}
}
}
for(auto [u, w] : adj[node]){
if(u == parent) continue;
st.upd(tin[u], tout[u] + 1, -w);
st.upd(1, tin[u], w);
st.upd(tout[u] + 1, n + 1, w);
reroot(u, node);
st.upd(tout[u] + 1, n + 1, -w);
st.upd(1, tin[u], -w);
st.upd(tin[u], tout[u] + 1, w);
}
}
void solve(int tc) {
cin >> n >> s >> q >> e;
for(int i = 1; i < n; i++){
int u, v;
ll w;
cin >> u >> v >> w;
edges.push_back({u, v});
adj[u].push_back({v, w});
adj[v].push_back({u, w});
}
for(int i = 0; i < s; i++){
int u;
cin >> u;
marked[u] = 1;
}
dfs(1, 0);
for(int i = 0; i < q; i++){
int u, R;
cin >> R >> u;
R--;
qrs[u].push_back({R, i});
}
st.init();
reroot(1, 0);
for(int i = 0; i < q; i++){
if(answ[i] == 1){
cout << "escaped\n";
}else if(answ[i] == 0){
cout << "oo\n";
}else{
cout << ans[i] << endl;
}
}
}
void precalc() {
}
int main() {
// SetIO("in");
// stress_test;
FastIO();
int test_case = 1;
// cin >> test_case;
auto start = chrono::steady_clock::now();
precalc();
int cnt = 1;
while (test_case--) {
solve(cnt++);
}
auto end = chrono::steady_clock::now();
std::chrono::duration<double> elapsed_seconds = end - start;
cerr << "Execution: " << elapsed_seconds.count() << endl;
return 0;
}
