import sys
input = sys.stdin.readline
sys.setrecursionlimit(10**8)
N,Q = map(int,input().split())
AB = [tuple(map(int,input().split())) for i in range(N-1)]
PX = [tuple(map(int,input().split())) for i in range(Q)]

es = [[] for _ in range(N)]
for a,b in AB:
    a,b = a-1,b-1
    es[a].append(b)
    es[b].append(a)

cs = [0] * N
def dfs(v,p=-1):
    if len(es[v])==1:
        cs[v] = 1
        return 1
    ret = 1
    for to in es[v]:
        if to==p: continue
        ret += dfs(to,v)
    cs[v] = ret
    return ret
dfs(0)

ans = 0
for p,x in PX:
    p -= 1
    ans += cs[p] * x
    print(ans)