#include <bits/stdc++.h>
using namespace std;
#define all(v) begin(v),end(v)
#define REP(i,a,b) for(int i=a;i<b;i++)
#pragma GCC optimize("O3")
using ii = pair<int,int>;
int main() {
ios_base::sync_with_stdio(0); cin.tie(0);
int n, m, q;
cin >> n >> m >> q;
vector<int> h(n,0), euler(n), c(m);
vector<vector<int>> adj(n);
REP(i,1,n) {
int a, b;
cin >> a >> b;
adj[a-1].push_back(b-1);
adj[b-1].push_back(a-1);
}
vector<vector<int>> sparse(18,vector<int>(2*n,0));
auto dfs = [cnt=0,&sparse,&adj,&h,&euler](auto &self, int x, int p) mutable -> void {
sparse[0][euler[x] = cnt++] = h[x];
for(auto i: adj[x])
if(i != p) {
h[i] = h[x] + 1;
self(self, i, x);
sparse[0][cnt++] = h[x];
}
};
dfs(dfs, 0, -1);
for(int i=1;i<18;i++)
for(int j=0;j<=2*n-(1<<i);j++)
sparse[i][j] = min(sparse[i-1][j],sparse[i-1][j+(1<<(i-1))]);
auto lca = [&sparse,&euler](int a, int b) {
if(a > b)
swap(a, b);
int l = 31 ^ __builtin_clz(b - a + 1);
return min(sparse[l][a], sparse[l][b-(1<<l)+1]);
};
REP(i,0,m) {
cin >> c[i];
c[i]--;
}
multiset<ii> s;
auto val = [&s,&h,&lca](set<ii>::iterator it) {
if(s.size() == 1)
return 0;
int ans = h[it->second];
if(it == s.begin()) {
int r1 = lca(next(it)->first,prev(s.end())->first);
int r2 = lca(it->first,next(it)->first);
ans += r1 - r2 - min(r1, r2);
} else if(it == prev(s.end())) {
int r1 = lca(prev(it)->first,s.begin()->first);
int r2 = lca(it->first,prev(it)->first);
ans += r1 - r2 - min(r1, r2);
} else {
int r1 = lca(it->first,next(it)->first);
int r2 = lca(it->first,prev(it)->first);
ans += min(r1, r2) - r1 - r2;
}
return ans;
};
auto ins = [&s,&val](ii x) -> int {
auto it = s.insert(x);
return val(it);
};
auto rem = [&s,&val](ii x) -> int {
auto it = s.find(x);
int ans = -val(it);
s.erase(it);
return ans;
};
auto qry = [cl=0,cr=-1,ans=1,&c,&euler,&ins,&rem](int ql, int qr) mutable -> int {
while(cr < qr) {
cr++;
ans += ins({euler[c[cr]],c[cr]});
}
while(cl > ql) {
cl--;
ans += ins({euler[c[cl]],c[cl]});
}
while(cr > qr) {
ans += rem({euler[c[cr]],c[cr]});
cr--;
}
while(cl < ql) {
ans += rem({euler[c[cl]],c[cl]});
cl++;
}
return ans;
};
vector<array<int,3>> qrs(q);
REP(i,0,q) {
cin >> qrs[i][0] >> qrs[i][1];
qrs[i][0]--;
qrs[i][1]--;
qrs[i][2] = i;
}
sort(all(qrs),[](array<int,3> a, array<int,3> b) {
if(a[0]/300 == b[0]/300)
return ((a[0]/300)&1?a[1]<b[1]:a[1]>b[1]);
return a[0]<b[0];
});
vector<int> ans(q);
REP(i,0,q)
ans[qrs[i][2]] = qry(qrs[i][0], qrs[i][1]);
for(int i=0;i<q;i++)
cout << ans[i] << "\n";
}
