#include <bits/stdc++.h>
using namespace std;
#define all(x) x.begin(), x.end()
const int mxN = 1e5 + 100;
const int mxB = 21;
vector<int> adj[mxN];
vector<int> euler;
pair<int, int> dp[mxN * 4][mxB];
int st[mxN], en[mxN], depth[mxN];
void dfs(int u = 1, int par = 0){
st[u] = (int) euler.size(), depth[u] = depth[par] + 1;
euler.push_back(u);
for(auto v : adj[u]){
if(v ^ par){
dfs(v, u);
euler.push_back(u);
}
}
en[u] = (int) euler.size();
euler.push_back(u);
}
void build(){
int n = (int) euler.size();
for(int i = 0; i < n; ++i){
dp[i][0] = {depth[euler[i]], euler[i]};
}
for(int j = 1; j < mxB; ++j){
for(int i = 0; i + (1 << j) - 1 < n; ++i){
dp[i][j] = min(dp[i][j - 1], dp[i + (1 << (j - 1))][j - 1]);
}
}
}
int lca(int u, int v){
int l = en[u], r = en[v];
if(l > r) swap(l, r);
int k = __lg(r - l + 1);
return min(dp[l][k], dp[r - (1 << k) + 1][k]).second;
}
int dist(int u, int v){
return depth[u] + depth[v] - 2 * depth[lca(u, v)];
}
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(nullptr); cout.tie(nullptr);
int n, m, q;
cin >> n >> m >> q;
vector<int> a(m + 1, 0);
for(int i = 1, u, v; i <= n - 1; ++i){
cin >> u >> v;
adj[u].push_back(v);
adj[v].push_back(u);
}
for(int i = 1; i <= m; ++i){
cin >> a[i];
}
dfs();
build();
while(q--){
int l, r;
cin >> l >> r;
long long ans = 0;
vector<int> vec;
for(int i = l; i <= r; ++i){
vec.push_back(a[i]);
}
sort(all(vec), [&](int x, int y){
return st[x] < st[y];
});
vec.push_back(vec[0]);
for(int i = 0; i < (int) vec.size() - 1; ++i){
ans += (long long) dist(vec[i], vec[i + 1]);
}
cout << ans / 2 + 1 << "\n";
}
return 0;
}
