//
#ifndef __SIZEOF_INT128__
#define __SIZEOF_INT128__
#endif
#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace chrono;
using namespace __gnu_pbds;
template <typename T> using oset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define rep(i, p, k) for(int i(p); i < (k); ++i)
#define per(i, p, k) for(int i(p); i > (k); --i)
#define sz(x) (int)(x).size()
#define sc static_cast
typedef long long ll;
typedef long double ld;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef __int128_t lll;
//#define int ll
template <typename T = int> using par = std::pair <T, T>;
#define fi first
#define se second
#define test int _number_of_tests(in()); while(_number_of_tests--)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define pb emplace_back
struct Timer {
string name{""};
time_point<high_resolution_clock> end, start{high_resolution_clock::now()};
duration<float, std::milli> dur;
Timer() = default;
Timer(string nm): name(nm) {}
~Timer() {
end = high_resolution_clock::now(); dur= end - start;
cout << "@" << name << "> " << dur.count() << " ms" << '\n';
}
};
template <typename T = int> inline T in()
{
static T x;
std::cin >> x;
return x;
}
std::string yn(bool b)
{
if(b) return "YES\n";
else return "NO\n";
}
template <typename F, typename S> std::ostream& operator<<(std::ostream& out, const std::pair <F, S>& par);
template <typename T> std::ostream& operator<< (std::ostream& out, const std::vector <T>& wek)
{
for(const auto& i : wek)out << i << ' ';
return out;
}
template <typename F, typename S> std::ostream& operator<<(std::ostream& out, const std::pair <F, S>& par)
{
out << '{'<<par.first<<", "<<par.second<<"}";
return out;
}
#define show(x) cerr << #x << " = " << x << '\n';
constexpr int maxn = 1e5 + 3, maxk = 20;
vector <int> gr[maxn];
int roz[maxn], hev[maxn], ojc[maxn], pok[maxn], jp[maxn][maxk];
void dfs(int w, int o = 0){
ojc[w] = o;
pok[w] = pok[o]+1;
roz[w] = 1;
int m(-1);
for(auto i: gr[w])if(i != o){
dfs(i, w);
roz[w] += roz[i];
if(roz[i] > m){
m = roz[i];
hev[w] = i;
}
}
}
int cha[maxn], poz[maxn];
vector <int> csk[maxn];
void df2(int w, int o = 0, int c = -1){
if(c == -1)c = w;
cha[w] = c;
poz[w] = sz(csk[c]);
csk[c].pb(w);
for(auto i: gr[w])if(i != o) df2(i, w, i==hev[w]?c:-1);
}
vector <ll> tr[maxn];
int trp[maxn];
void add(int w, int c){
int k(cha[w]), g(poz[w]+trp[k]);
while(g){
tr[k][g] += c;
g /= 2;
}
}
ll su1(int w, int p){
ll o(0);
while(pok[w] > pok[p]){
int k(cha[w]), a(trp[k]+(k==cha[p]?poz[p]:-1)), b(trp[k]+poz[w]+1);
while(a+1 != b){
if(a % 2 == 0)o += tr[k][a+1];
if(b % 2 == 1)o += tr[k][b-1];
a /= 2; b /= 2;
}
w = ojc[cha[w]];
}
return o;
}
int lca(int a, int b);
ll sum(int a, int b){
int l(lca(a,b));
return su1(a,l)+su1(b,l);
}
int oj(int w, int k){
if(jp[w][k])return jp[w][k];
return jp[w][k] = oj(oj(w,k-1),k-1);
}
int lca(int a, int b){
if(pok[a] < pok[b])swap(a, b);
int k(maxk-1);
while(pok[a] > pok[b]){
while(k&&pok[oj(a, k)] <= pok[b])--k;
a = oj(a, k);
}
k = maxk-1;
while(a != b){
while(k&&oj(a,k) == oj(b,k))--k;
a = oj(a, k); b = oj(b, k);
}
return a;
}
std::int32_t main()
{
std::cout.tie(nullptr); //for luck
std::cin.tie(nullptr); std::ios_base::sync_with_stdio(0);
int n(in()), m(in()), q(in());
vector <pair <int, int>> kr;
rep(i, 1, n){
int a(in()), b(in());
kr.pb(a,b);
gr[a].pb(b);
gr[b].pb(a);
}
dfs(1);
rep(i, 1, n+1)jp[i][0] = ojc[i]; jp[1][0] = 1;
df2(1);
rep(i, 1, n+1)if(i == cha[i]){
trp[i] = 1;
while(trp[i] < sz(csk[i]))trp[i]*=2;
tr[i].resize(trp[i]*2);
}
vector<int> dol(n);
rep(i, 0, n-1)dol[i+1] = (pok[kr[i].first] < pok[kr[i].second] ? kr[i].second : kr[i].first);
vector<pair <int, int>> v(m);
rep(i, 0, m)cin >> v[i].second >> v[i].first;
sort(all(v));
vector <int> a(q), b(q), c(q), p(q), k(q);
vector <ll> d(q);
rep(i, 0, q){
cin >> a[i] >> b[i] >> c[i] >> d[i];
p[i] = 0; k[i] = m;
}
while(1){
bool r(0);
vector <vector <int>> zap(m+1);
rep(i, 0, q)if(p[i] != k[i]){
zap[(p[i]+k[i]+1)/2].pb(i);
r = 1;
}
if(!r)break;
rep(i, 0, m+1){
for(auto j: zap[i]){
if(sum(a[j],b[j]) <= d[j])p[j] = i;
else k[j] = i-1;
}
if(i < m)add(dol[v[i].second], v[i].first);
}
rep(i, 0, m)add(dol[v[i].second], -v[i].first);
}
vector <int> odp(q);
vector <vector <int>> pyt(m+1);
rep(i, 0, q)pyt[p[i]].pb(i);
rep(i, 0, m) add(dol[v[i].second], 1);
rep(i, 0, m+1){
for(auto j: pyt[i])odp[j] = max(-1ll, c[j]-sum(a[j],b[j]));
if(i < m)add(dol[v[i].second], -1);
}
rep(i, 0, q)cout << odp[i] <<'\n';
return 0;
}
