#include<bits/stdc++.h>
#define fori(i,a,b) for(int i=a;i<=b;i++)
#define int long long
#define pb push_back
using namespace std;
typedef pair<int,int> ii;
typedef tuple<int,int,int> tp;
const int M=1e6+10;
const int N=1e3+10;
const int mod=1e9+7;
int n,m,q,c[M];
vector<int> ke[M];
int num[M],tail[M],cnt = 0, up[M][20], d[M];
void dfs(int u,int p)
{
num[u] = ++cnt;
for(int i =1;i <= 18; i++) up[u][i] = up[up[u][i-1]][i-1];
for(int v : ke[u]) {
if(v == p) continue;
up[v][0] = u;
d[v] = d[u] + 1;
dfs(v,u);
}
tail[u] = cnt;
}
bool anc(int u,int v)
{
return num[u] <= num[v] && tail[u] >= tail[v];
}
int lca(int u,int v)
{
if(anc(u,v)) return u;
if(anc(v,u)) return v;
for(int i = 18;i >=0 ; i--) if(!anc(up[u][i],v)) u = up[u][i];
return up[u][0];
}
int dist(int u,int v)
{
int x = lca(u,v);
return d[u] + d[v] - 2 * d[x];
}
bool cmp(const int &a,const int &b)
{
return num[a] < num[b];
}
int32_t main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
if(fopen("1.inp","r"))
{
freopen("1.inp","r",stdin);
freopen("1.out","w",stdout);
}
#define task "tourism"
if(fopen(task".inp","r"))
{
freopen(task".inp","r",stdin);
freopen(task".out","w",stdout);
}
cin >> n >> m >> q;
for(int i = 1;i <= n - 1; i++) {
int u,v;
cin >> u >> v;
ke[u].pb(v);
ke[v].pb(u);
}
up[1][0] = 1;
dfs(1,0);
for(int i = 1;i <= m; i++) cin >> c[i];
while(q--) {
int l,r;
cin >> l >> r;
// cout << l << " " << r << "\n";
vector<int> Q;
for(int i = l;i <= r; i++) Q.pb(c[i]);
sort(Q.begin(),Q.end(),cmp);
int sz = Q.size();
for(int i = 0;i <= sz - 2; i++) {
Q.pb(lca(Q[i],Q[i + 1]));
}
//for(int v : Q) cout << v << " ";
sort(Q.begin(),Q.end(),cmp);
Q.resize(unique(Q.begin(),Q.end()) - Q.begin());
stack<int> sk;
int kq = 0;
for(int v : Q) {
while(!sk.empty() && !anc(sk.top(),v)) sk.pop();
if(!sk.empty()) kq += dist(sk.top(),v);
sk.push(v);
}
cout << kq + 1 << "\n";
}
}
