#include <cassert>
#include <cmath>
#include <algorithm>
#include <iostream>
#include <iomanip>
#include <climits>
#include <map>
#include <queue>
#include <set>
#include <cstring>
#include <vector>

using namespace std;
typedef long long ll;

const int MAX_N = 100010;
ll C[MAX_N];
vector<int> E[MAX_N];

ll dfs(int v, vector<bool> &visited) {
  ll cnt = 1;
  visited[v] = true;

  for (int u : E[v]) {
    if (visited[u]) continue;

    cnt += dfs(u, visited);
  }

  return C[v] = cnt;
}

int main() {
  int N, Q;
  cin >> N >> Q;

  for (int i = 0; i < N - 1; ++i) {
    int a, b;
    cin >> a >> b;

    E[a].push_back(b);
    E[b].push_back(a);
  }

  vector<bool> visited(N + 1, false);
  dfs(1, visited);
  ll ans = 0;

  for (int i = 0; i < Q; ++i) {
    int p, x;
    cin >> p >> x;

    ans += C[p] * x;
    cout << ans << endl;
  }

  return 0;
}