#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define st first
#define nd second
#define pb push_back
#define all(a) a.begin(),a.end()
#define rep(a,b) for(int a = 0;a<b;a++)
const int inf = 1e9;
const ll infl = 1e18;
bool vis[100000];
vector<int> gr[100000];
int jp[20][100000];
int pr[100000];
int rpr[100000];
int d[100000];
int cpr = 0;
void dfs(int v,int cd)
{
pr[v] = cpr;
d[v] = cd;
rpr[cpr] = v;
cpr++;
vis[v] = true;
for(int i : gr[v])
{
if(!vis[i])
{
dfs(i,cd+1);
jp[0][i] = v;
}
}
}
int lca(int a,int b)
{
if(d[a] < d[b])
{
swap(a,b);
}
for(int i = 19;i>=0;i--)
{
if(d[a] - (1<<i) >= d[b])
{
a = jp[i][a];
}
}
if(a==b)return a;
for(int i = 19;i>=0;i--)
{
if(jp[i][a] != jp[i][b])
{
a = jp[i][a];
b = jp[i][b];
}
}
return jp[0][a];
}
int c[100000];
int main()
{
int n,m,q;
cin>>n>>m>>q;
rep(i,n-1)
{
int a,b;
cin>>a>>b;
a--;b--;
gr[a].pb(b);
gr[b].pb(a);
}
rep(i,m)
{
cin>>c[i];
c[i]--;
}
jp[0][0] = 0;
dfs(0,0);
rep(qq,q)
{
int ans = 0;
int l,r;
cin>>l>>r;
l--;r--;
vector<int> cc;
for(int i = l;i<=r;i++)
{
cc.pb(pr[c[i]]);
}
sort(all(cc));
int plca = rpr[cc[0]];
for(int i = 1;i<cc.size();i++)
{
ans += d[rpr[cc[i]]] - d[lca(rpr[cc[i]],rpr[cc[i-1]])];
ans += d[plca] - d[lca(rpr[cc[i]],plca)];
plca = lca(rpr[cc[i]],plca);
}
cout<<ans+1<<"\n";
}
}
