import java.io.PrintWriter
import java.util.*
import kotlin.math.*

fun PrintWriter.solve() {
    val n = nextInt()
    val q = nextInt()
    val adj = Array(n) { mutableListOf<Int>() }
    for (i in 0 until n - 1) {
        val v1 = nextInt() - 1
        val v2 = nextInt() - 1
        adj[v1].add(v2)
        adj[v2].add(v1)
    }
    val size = Array(n) { 1 }
    fun dfs(v: Int, p: Int): Int {
        for (w in adj[v]) {
            if (w != p) {
                size[v] += dfs(w, v)
            }
        }
        return size[v]
    }
    dfs(0, -1)
    var sum = 0L
    for (i in 0 until q) {
        val p = nextInt() - 1
        val x = nextLong()
        sum += size[p] * x
        println(sum)
    }
}

fun main2() {
    val writer = PrintWriter(System.out, false)
    writer.solve()
    writer.flush()
}

fun main() = Thread(null, ::main2, "", 64 * 1024 * 1024)
        .apply { setUncaughtExceptionHandler { _, e -> e.printStackTrace(); kotlin.system.exitProcess(1) } }
        .apply { start() }.join()

// region Scanner
private var st = StringTokenizer("")
private val br = System.`in`.bufferedReader()

fun next(): String {
    while (!st.hasMoreTokens()) st = StringTokenizer(br.readLine())
    return st.nextToken()
}

fun nextInt() = next().toInt()
fun nextLong() = next().toLong()
fun nextLine() = br.readLine()
fun nextDouble() = next().toDouble()
// endregion