#include "bits/stdc++.h"

#define int long long

using namespace std;
using ll = long long;
using P = pair<ll, ll>;
const ll INF = (1LL << 61);
ll mod = 1000000007;
int N, Q;
vector<int>G[100010];
vector<int>s;
void dfs(int v, int p) {
	for (auto nv : G[v]) {
		if (nv == p)continue;
		dfs(nv, v);
	}
	s[v] = 1;
	for (auto c : G[v]) {
		if (c == p)continue;
		s[v] += s[c];
	}
}
signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin >> N >> Q;
	s.resize(N);
	for (int i = 0; i < N - 1; i++) {
		int a, b; cin >> a >> b; a--; b--;
		G[a].push_back(b);
		G[b].push_back(a);
	}
	dfs(0, -1);
	int now = 0;
	for (int _ = 0; _ < Q; _++) {
		int p, x; cin >> p >> x; p--;
		now += s[p] * x;
		cout << now << endl;
	}
	return 0;


}