import sys
sys.setrecursionlimit(10**5)
n,q=map(int,input().split())
g=[[] for _ in range(n)]
for _ in range(n-1):
    a,b=map(int,input().split())
    g[a-1].append(b-1)
    g[b-1].append(a-1)
subnode=[[] for _ in range(n)]
def dfs(now,pre):
    subnode[now]+=1
    for to in g[now]:
        if to==pre:
            continue
        dfs(to,now)
        subnode[now]+=subnode[to]
dfs(0,-1)
ans=0
for _ in range(q):
    p,x=map(int,input().split())
    ans+=subnode[p-1]*x
    print(ans)