#include<iostream>
#include<vector>
using namespace std;
int N,Q;
vector<int>G[1<<17];
int ch[1<<17];
int dfs(int u,int p)
{
	ch[u]=1;
	for(int v:G[u])if(v!=p)ch[u]+=dfs(v,u);
	return ch[u];
}
main()
{
	cin>>N>>Q;
	for(int i=1;i<N;i++)
	{
		int a,b;cin>>a>>b;
		G[a].push_back(b);
		G[b].push_back(a);
	}
	dfs(1,0);
	long ans=0;
	for(int i=0;i<Q;i++)
	{
		int p,x;cin>>p>>x;
		cout<<(ans+=(long)x*ch[p])<<endl;
	}
}