pub mod io {
    use std::io::{BufRead, ErrorKind};

    pub fn scan<R: BufRead>(r: &mut R) -> Vec<u8> {
        let mut res = Vec::new();
        loop {
            let buf = match r.fill_buf() {
                Ok(buf) => buf,
                Err(e) if e.kind() == ErrorKind::Interrupted => continue,
                Err(e) => panic!(e), 
            };
            let (done, used, buf) = {
                match buf.iter().position(u8::is_ascii_whitespace) {
                    Some(i) => (i > 0 || res.len() > 0, i + 1, &buf[..i]),
                    None => (buf.is_empty(), buf.len(), buf),
                }
            };
            res.extend_from_slice(buf);
            r.consume(used);
            if done { return res; }
        }
    }

    #[macro_export]
    macro_rules! scan {
        ($r:expr, [$t:tt; $n:expr]) => {
            (0..$n).map(|_| scan!($r, $t)).collect::<Vec<_>>()
        };
        ($r:expr, [$t:tt]) => {
            scan!($r, [$t; scan!($r, usize)])
        };
        ($r:expr, ($($t:tt),*)) => {
            ($(scan!($r, $t)),*)
        };
        ($r:expr, Usize1) => {
            scan!($r, usize) - 1
        };
        ($r:expr, Bytes) => {
            io::scan($r)
        };
        ($r:expr, String) => {
            String::from_utf8(scan!($r, Bytes)).unwrap()
        };
        ($r:expr, $t:ty) => {
            scan!($r, String).parse::<$t>().unwrap()
        };
    }

    #[macro_export]
    macro_rules! input {
        ($($($v:ident)* : $t:tt),* $(,)?) => {
            let stdin = std::io::stdin();
            let ref mut reader = std::io::BufReader::new(stdin.lock());
            $(let $($v)* = scan!(reader, $t);)*
        };
    }
}

struct Dfs {
    graph: Vec<Vec<usize>>,
    count: Vec<u64>,
}

impl Dfs {
    fn search(&mut self, prev: usize, from: usize) {
        let mut count = 1;
        for to in self.graph[from].clone() {
            if to == prev {
                continue;
            }
            self.search(from, to);
            count += self.count[to];
        }
        self.count[from] = count;
    }
}

use std::io::Write;

fn main() {
    input! {
        n: usize, q: usize,
        edges: [(Usize1, Usize1); n - 1],
        queries: [(Usize1, u64); q],
    }

    let mut graph = vec![vec![]; n];
    for (a, b) in edges {
        graph[a].push(b);
        graph[b].push(a);
    }
    let count = vec![0; n];
    let mut dfs = Dfs { graph, count };
    dfs.search(!0, 0);

    let stdout = std::io::stdout();
    let mut writer = std::io::BufWriter::new(stdout.lock());

    let mut ans = 0;
    for (p, x) in queries {
        ans += dfs.count[p] * x;
        writeln!(writer, "{}", ans).ok();
    }
}