#include <bits/stdc++.h>
using namespace std;
#ifdef nguyn_debug
#include "debug.h"
#else
#define debug(...)
#endif // LOCAL
#define ll long long
#define F first
#define S second
#define pb push_back
#define pii pair<int, int>
#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()
const int N = 1e5 + 5;
const int mod = 1e9 + 7;
const ll inf = 1e18;
int tin[N], timedfs, rmq[N][20];
pii rmq_euler[N * 2][20];
int h[N], sz[N];
int n, m, q;
int c[N];
vector<pii> ev[N];
vector<int> pos[N];
vector<int> g[N];
vector<pii> add_ev[N];
int res[N];
set<int> st;
void predfs(int u, int p) {
tin[u] = ++timedfs;
sz[u] = 1;
rmq_euler[timedfs][0] = {h[u], u};
for (int v : g[u]) {
if (v == p) continue;
h[v] = h[u] + 1;
predfs(v, u);
sz[u] += sz[v];
rmq_euler[++timedfs][0] = {h[u], u};
}
}
int get_lca(int u, int v) {
if (tin[u] > tin[v]) swap(u, v);
int lg = 31 - __builtin_clz(tin[v] - tin[u] + 1);
return min(rmq_euler[tin[u]][lg], rmq_euler[tin[v] - (1 << lg) + 1][lg]).S;
}
int get_range_lca(int u, int v) {
int lg = 31 - __builtin_clz(v - u + 1);
return get_lca(rmq[u][lg], rmq[v - (1 << lg) + 1][lg]);
}
void add_to_st(int i, int delta) {
auto it = st.insert(i).F;
int pre = *prev(it) + 1;
int nxt = *next(it) - 1;
add_ev[pre].pb({nxt, delta});
add_ev[pre].pb({i - 1, - delta});
add_ev[i + 1].pb({nxt, - delta});
}
void add_node(int u, int p, int delta) {
for (int i : pos[u]) {
add_to_st(i, delta);
}
for (int v : g[u]) {
if (v == p) continue;
add_node(v, u, delta);
}
}
void erase_node(int u, int p) {
for (int i : pos[u]) st.erase(st.find(i));
for (int v : g[u]) {
if (v == p) continue;
erase_node(v, u);
}
}
void dfs(int u, int p, int dep, bool keep) {
int big = 0;
// debug(u, dep);
for (int v : g[u]) {
if (v == p) continue;
if (sz[v] > sz[big]) big = v;
}
for (int v : g[u]) {
if (v == p || v == big) continue;
dfs(v, u, 1, 0);
}
if (big) dfs(big, u, dep + 1, 1);
for (int i : pos[u]) {
add_to_st(i, dep);
}
for (int v : g[u]) {
if (v == p || v == big) continue;
add_node(v, u, dep);
}
if (!keep) erase_node(u, p);
}
struct BIT {
int n;
vector<int> bit;
BIT() {}
BIT (int n) : n(n) {
bit.assign(n + 3, 0);
}
void update(int id, int val) {
for (int i = id; i <= n; i += (i & -i)) bit[i] += val;
}
int get(int id) {
int res = 0;
for (int i = id; i > 0; i -= (i & -i)) {
res += bit[i];
}
return res;
}
} bit;
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> n >> m >> q;
for (int i = 1; i < n; i++) {
int u, v;
cin >> u >> v;
g[u].pb(v);
g[v].pb(u);
}
predfs(1, 0);
for (int i = 1; i < 20; i++) {
for (int j = 1; j + (1 << i) - 1 <= timedfs; j++) {
rmq_euler[j][i] = min(rmq_euler[j][i - 1], rmq_euler[j + (1 << (i - 1))][i - 1]);
}
}
for (int i = 1; i <= m; i++) {
cin >> c[i]; pos[c[i]].pb(i);
rmq[i][0] = c[i];
}
for (int i = 1; i < 20; i++) {
for (int j = 1; j + (1 << i) - 1 <= m; j++) {
rmq[j][i] = get_lca(rmq[j][i - 1], rmq[j + (1 << (i - 1))][i - 1]);
}
}
for (int i = 1; i <= q; i++) {
int l, r;
cin >> l >> r;
ev[l].pb({r, i});
}
st.insert(0);
st.insert(m + 1);
dfs(1, 0, 1, 1);
bit = BIT(m);
for (int i = 1; i <= m; i++) {
for (auto it : add_ev[i]) {
int r = it.F;
int val = it.S;
// debug(i, r, val);
bit.update(i, val);
bit.update(r + 1, - val);
}
for (auto it : ev[i]) {
int r = it.F;
int id = it.S;
// debug(bit.get(r), get_range_lca(i, r), i, r);
res[id] = bit.get(r) - h[get_range_lca(i, r)];
}
}
for (int i = 1; i <= q; i++) {
cout << res[i] << '\n';
}
}
