#include <bits/stdc++.h>
#define inf 1000000007
#define mod 1000000007
#define lowbit(x) (x&(-x))
#define int long long
// #pragma GCC optimize("Ofast","inline","-ffast-math")
// #pragma GCC target("avx,sse2,sse3,sse4,mmx")
using namespace std;
template <typename T> void read(T &x){
	x=0;char ch=getchar();int fh=1;
	while (ch<'0'||ch>'9'){if (ch=='-')fh=-1;ch=getchar();}
	while (ch>='0'&&ch<='9')x=x*10+ch-'0',ch=getchar();
	x*=fh;
}
template <typename T> void write(T x) {
	if (x<0) x=-x,putchar('-');
	if (x>9) write(x/10);
	putchar(x%10+'0');
}
template <typename T> void writeln(T x) {
	write(x);
	puts("");
}
int n,q,rt,all,tot;
int h[200005],e[400005],w[400005],ne[400005],idx;
int siz[200005],maxp[200005];
int dist[200005],bit[200005],ans[1000005];
bool vis[200005];
struct node
{
	int l,r,dist;
	bool operator<(const node &o) const
	{
		return l>o.l;
	}
}opr[1000005];
struct query
{
	int l,r,id;
	bool operator<(const query &o) const
	{
		return l>o.l;
	}
}qry[1000005];
void change(int x,int y)
{
	while(x<=n)
	{
		bit[x]=min(bit[x],y);
		x+=lowbit(x);
	}
}
int ask(int x)
{
	int res=1ll*inf*inf;
	while(x)
	{
		res=min(res,bit[x]);
		x-=lowbit(x);
	}
	return res;
}
void getrt(int x,int fa)
{
	siz[x]=1;maxp[x]=0;
	for(int i=h[x];~i;i=ne[i])
	{
		int j=e[i];
		if(j==fa||vis[j]) continue;
		getrt(j,x);siz[x]+=siz[j];
		maxp[x]=max(maxp[x],siz[j]);
	}
	maxp[x]=max(maxp[x],all-siz[x]);
	if(maxp[rt]>maxp[x]) rt=x;
}
void add(int a,int b,int c)
{
	e[idx]=b,w[idx]=c;ne[idx]=h[a],h[a]=idx++;
}
pair<int,int> d[1000005];
int len;
void dfs(int x,int fa,int dis)
{
	d[++len]={dis,x};dist[x]=dis;
	for(int i=h[x];~i;i=ne[i])
	{
		int j=e[i];
		if(j==fa||vis[j]) continue;
		dfs(j,x,dis+w[i]);
	}
}
void solve(int x)
{
	len=1;d[1]={0,x};dist[x]=0;
	for(int i=h[x];~i;i=ne[i])
	{
		int j=e[i];
		if(vis[j]) continue;
		dfs(j,x,w[i]);
	}
	sort(d+1,d+len+1);
	set<int> st={-inf,inf};
	for(int i=1;i<=len;++i)
	{
		int pre=*prev(st.lower_bound(d[i].second));
		if(pre!=-inf)
			opr[++tot]={pre,d[i].second,dist[d[i].second]+dist[pre]};
		int suf=*st.lower_bound(d[i].second);
		if(suf!=inf)
			opr[++tot]={d[i].second,suf,dist[d[i].second]+dist[suf]};
		st.insert(d[i].second);
	}
}
void divide(int x)
{
	vis[x]=1;
	solve(x);
	for(int i=h[x];~i;i=ne[i])
	{
		int j=e[i];
		if(vis[j]) continue;
		maxp[rt=0]=all=siz[j];
		getrt(j,0);getrt(rt,0);
		divide(rt);
	}
}
signed main()
{
	// freopen(".in","r",stdin);
	// freopen(".out","w",stdout);
	read(n);memset(h,-1,sizeof(h));
	memset(bit,0x3f,sizeof(bit));
	for(int i=1;i<n;++i)
	{
		int a,b,c;
		read(a);read(b);read(c);
		add(a,b,c);add(b,a,c);
	}
	maxp[rt=0]=all=n;
	getrt(1,0);getrt(rt,0);
	divide(rt);
	sort(opr+1,opr+tot+1);
	read(q);
	for(int i=1;i<=q;++i)
		read(qry[i].l),read(qry[i].r),qry[i].id=i;
	sort(qry+1,qry+q+1);
	for(int i=1,j=1;i<=q;++i)
	{
		while(j<=tot&&opr[j].l>=qry[i].l)
			change(opr[j].r,opr[j].dist),++j;
		ans[qry[i].id]=ask(qry[i].r);
	}
	for(int i=1;i<=q;++i)
	{
		if(ans[i]>1ll*inf*inf/2) ans[i]=-1;
		writeln(ans[i]);
	}
	return 0;
}