/* -*- coding: utf-8 -*-
 *
 * 1637.cc:  No.1637 Easy Tree Query - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_N = 100000;

/* typedef */

typedef long long ll;
typedef vector<int> vi;

/* global variables */

vi nbrs[MAX_N];
int ps[MAX_N], cis[MAX_N], ss[MAX_N];

/* subroutines */

/* main */

int main() {
  int n, qn;
  scanf("%d%d", &n, &qn);

  for (int i = 1; i < n; i++) {
    int a, b;
    scanf("%d%d", &a, &b);
    a--, b--;
    nbrs[a].push_back(b);
    nbrs[b].push_back(a);
  }

  ps[0] = -1;
  for (int u = 0; u >= 0;) {
    vi &nbru = nbrs[u];
    int up = ps[u];

    if (cis[u] < nbru.size()) {
      int v = nbru[cis[u]++];
      if (v != up) {
	ps[v] = u;
	u = v;
      }
    }
    else {
      ss[u]++;
      if (up >= 0) ss[up] += ss[u];
      u = up;
    }
  }

  ll sum = 0;
  while (qn--) {
    int p, x;
    scanf("%d%d", &p, &x);
    p--;

    sum += (ll)x * ss[p];
    printf("%lld\n", sum);
  }

  return 0;
}