import sys
input = lambda: sys.stdin.readline().rstrip()

class RootedTree:

  def __init__(self, G: list, root: int):
    self._n = len(G)
    self._G = G
    self._root = root
    self._height = -1
    self._toposo = []
    self._dist = []
    self._descendant_num = []
    self._child = []
    self._child_num = []
    self._parents = []
    self._diameter = -1
    self._bipartite_graph = []

    self._calc_dist_toposo()
    # self._calc_child_parents()

  def __len__(self) -> int:
    "Return the number of vertex of self. / O(1)"
    return self._n

  def __str__(self) -> str:
    "Print Rooted Tree. / O(N) or O(1)"
    self._calc_child_parents()
    ret = ["<RootedTree> ["]
    ret.extend(
      [f'  dist:{d} - v:{str(i).zfill(2)} - p:{str(self._parents[i]).zfill(2)} - child:{self._child[i]}'
       for i,d in sorted(enumerate(self._dist), key=lambda x: x[1])]
      )
    ret.append(']')
    return '\n'.join(ret)

  def _calc_dist_toposo(self) -> None:
    "Calc dist and toposo. / O(N)"
    todo = [self._root]
    self._dist = [-1] * self._n
    self._dist[self._root] = 0
    self._toposo = [self._root]

    while todo:
      v = todo.pop()
      d = self._dist[v]
      for x,c in self._G[v]:
        if self._dist[x] != -1:
          continue
        self._dist[x] = d + c
        todo.append(x)
        self._toposo.append(x)
    return

  def _calc_child_parents(self) -> None:
    "Calc child and parents. / O(N)"
    if self._child and self._child_num and self._parents:
      return
    self._child_num = [0] * self._n
    self._child = [[] for _ in range(self._n)]
    self._parents = [-1] * self._n

    for v in self._toposo[::-1]:
      for x,c in self._G[v]:
        if self._dist[x] < self._dist[v]:
          self._parents[v] = x
          continue
        self._child[v].append(x)
        self._child_num[v] += 1
    return

  def get_dist(self) -> list:
    "Return dist. / O(N)"
    return self._dist

  def get_toposo(self) -> list:
    "Return toposo. / O(N)"
    return self._toposo

  def get_height(self) -> int:
    "Return height. / O(N)"
    if self._height > -1:
      return self._height
    self._height = max(self._dist)
    return self._height

  def get_descendant_num(self) -> list:
    "Return descendant_num. / O(N)"
    if self._descendant_num:
      return self._descendant_num
    self._descendant_num = [1] * self._n

    for v in self._toposo[::-1]:
      for x,c in self._G[v]:
        if self._dist[x] < self._dist[v]:
          continue
        self._descendant_num[v] += self._descendant_num[x]

    for i in range(self._n):
      self._descendant_num[i] -= 1
    return self._descendant_num

  def get_child(self) -> list:
    "Return child / O(N)"
    if self._child:
      return self._child
    self._calc_child_parents()
    return self._child

  def get_child_num(self) -> list:
    "Return child_num. / O(N)"
    if self._child_num:
      return self._child_num
    self._calc_child_parents()
    return self._child_num

  def get_parents(self) -> list:
    "Return parents. / O(N)"
    if self._parents:
      return self._parents
    self._calc_child_parents()
    return self._parents

  def get_diameter(self) -> int:
    "Return diameter of tree. / O(N)"
    if self._diameter > -1:
      return self._diameter
    s = self._dist.index(self.get_height())
    todo = [s]
    ndist = [-1] * self._n
    ndist[s] = 0
    while todo:
      v = todo.pop()
      d = ndist[v]
      for x, c in self._G[v]:
        if ndist[x] != -1:
          continue
        ndist[x] = d + c
        todo.append(x)
    self._diameter = max(ndist)
    return self._diameter

  def get_bipartite_graph(self) -> list:
    "Return [1 if root else 0]. / O(N)"
    if self._bipartite_graph:
      return self._bipartite_graph
    self._bipartite_graph = [-1] * self._n
    self._bipartite_graph[self._root] = 1
    todo = [self._root]
    while todo:
      v = todo.pop()
      nc = 0 if self._bipartite_graph[v] else 1
      for x,_ in self._G[v]:
        if self._bipartite_graph[x] != -1:
          continue
        self._bipartite_graph[x] = nc
        todo.append(x)
    return self._bipartite_graph

#  -----------------------  #

n, q = map(int, input().split())
G = [[] for _ in range(n)]
for _ in range(n-1):
  a, b = map(int, input().split())
  a -= 1
  b -= 1
  G[a].append((b, 1))
  G[b].append((a, 1))

tree = RootedTree(G, 0)
dnum = tree.get_descendant_num()

now = 0
for _ in range(q):
  p, x = map(int, input().split())
  p -= 1
  now += (dnum[p]+1) * x
  print(now)