#include <bits/stdc++.h>
using namespace std;
constexpr size_t N = 100000, LGN = 18;
size_t c[N], e[N], anc[LGN][N], h[N], preorder[N];
vector<size_t> g[N];
size_t traverse(size_t u, size_t p, size_t i = 0)
{
preorder[u] = i++;
for (auto const &v : g[u])
if (v != p)
{
h[v] = h[u] + 1;
anc[0][v] = u;
for (size_t i = 1; i < LGN; ++i)
anc[i][v] = anc[i - 1][anc[i - 1][v]];
i = traverse(v, u, i);
}
return i;
}
size_t lift(size_t u, size_t d)
{
size_t z = 0;
while (d)
{
if (d & 1)
u = anc[z][u];
++z;
d >>= 1;
}
return u;
}
size_t lca(size_t u, size_t v)
{
if (h[u] < h[v])
swap(u, v);
u = lift(u, h[u] - h[v]);
if (u == v)
return u;
for (size_t i = LGN - 1; i < LGN; --i)
if (anc[i][u] != anc[i][v])
u = anc[i][u], v = anc[i][v];
return anc[0][u];
}
size_t distance(size_t u, size_t v)
{
return h[u] + h[v] - (h[lca(u, v)] << 1);
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
size_t n, m, q;
cin >> n >> m >> q;
for (size_t i = 0; i < n - 1; ++i)
{
size_t u, v;
cin >> u >> v;
g[u - 1].push_back(v - 1);
g[v - 1].push_back(u - 1);
}
traverse(0, -1);
for (size_t i = 0; i < m; ++i)
cin >> c[i], --c[i];
while (q--)
{
size_t l, r;
cin >> l >> r, --l, --r;
memcpy(e + l, c + l, (r - l + 1) * sizeof *c);
sort(e + l, e + r + 1, [](size_t u, size_t v)
{ return preorder[u] < preorder[v]; });
size_t distance_sum = distance(e[l], e[r]);
for (size_t i = l; i < r; ++i)
distance_sum += distance(e[i], e[i + 1]);
cout << (distance_sum >> 1) + 1 << '\n';
}
}
