#include<bits/stdc++.h>
#include <atcoder/all>
#ifdef LOCAL
#include <debug_print.hpp>
#define debug(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (static_cast<void>(0))
#endif
using namespace atcoder;
using mint=modint998244353;
using namespace std;
using ll=long long;
using ul=unsigned long long;
int dx[8] = {-1, 1, 0, 0, -1, -1, 1, 1};
int dy[8] = {0, 0, -1, 1, -1, 1, -1, 1};
using Graph=vector<vector<int>>;
ll op(ll a,ll b){return min(a,b);}
ll e(){return 2e9;}
int main(){
    int N,Q;
    cin>>N>>Q;
    vector<vector<int>>G(N);
    for(int i=0;i<N-1;i++){
        int a,b;
        cin>>a>>b;
        a--,b--;
        G[a].push_back(b),G[b].push_back(a);
    }
    vector<ll>dp(N,1);
    vector<bool>vi(N);
    auto dfs=[&](auto dfs,int i)->void {
        vi[i]=true;
        for(auto ni:G[i]){
            if(vi[ni])continue;
            dfs(dfs,ni);
            dp[i]+=dp[ni];
        }
    };
    dfs(dfs,0);
    ll ans=0;
    while(Q--){
        int a;ll c;
        cin>>a>>c;
        a--;
        ans+=dp[a]*c;
        cout<<ans<<endl;
    }
}