#include <ctype.h>
#include <vector>
#include <cstdio>
#define N 305000
typedef long long LL;using std::vector;
struct cmt
{int l,r;LL Size;
}tr[N*20];
inline void Read(int &x)
{register char ch=getchar();for(x=0;!isdigit(ch);ch=getchar());for(;isdigit(ch);x=x*10+ch-'0',ch=getchar());
}
LL ans;
int min(int a,int b) {return a>b?b:a;}
int max(int a,int b) {return a>b?a:b;}
vector<int>edge[N];
int t[N],dfn[N],l[N],r[N],n,q,dep[N],tim,siz[N],tot;
void dfs(int x,int fa)
{l[x]=++tim;dfn[tim]=x;dep[x]=dep[fa]+1;siz[x]=0;for(int i=0;i<edge[x].size();++i){int v=edge[x][i];if(v!=fa){dfs(v,x);siz[x]+=siz[v]+1;}}r[x]=tim;
}
void update(int l,int r,int x,int &y,int a,int b)
{y=++tot;tr[y].Size=tr[x].Size+b;if(l==r) return;tr[y].l=tr[x].l;tr[y].r=tr[x].r;int mid=(l+r)>>1;if(a<=mid) update(l,mid,tr[x].l,tr[y].l,a,b);else update(mid+1,r,tr[x].r,tr[y].r,a,b);
}
LL ask(int l,int r,int x,int y,int a,int b)
{if(l==a&&r==b) return tr[y].Size-tr[x].Size;int mid=(l+r)>>1;if(a>mid) return ask(mid+1,r,tr[x].r,tr[y].r,a,b);else if(b<=mid) return ask(l,mid,tr[x].l,tr[y].l,a,b);else return ask(l,mid,tr[x].l,tr[y].l,a,mid)+ask(mid+1,r,tr[x].r,tr[y].r,mid+1,b);
}
int main(int argc,char *argv[])
{freopen("laugh.in","r",stdin);freopen("laugh.out","w",stdout);Read(n);Read(q);for(int u,v,i=1;i<n;++i){Read(u);Read(v);edge[u].push_back(v); edge[v].push_back(u); }dfs(1,1);for(int i=1;i<=n;++i) update(1,n,t[i-1],t[i],dep[dfn[i]],siz[dfn[i]]);for(int p,k;q--;){Read(p);Read(k);ans=0;ans=(LL)siz[p]*min(dep[p]-1,k);if(dep[p]!=n) ans+=ask(1,n,t[l[p]-1],t[r[p]],dep[p]+1,min(n,dep[p]+k));printf("%lld\n",ans);}return 0;
}