#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define watch(x) cout<<(#x)<<"="<<(x)<<endl
#define mset(d,val) memset(d,val,sizeof(d))
#define setp(x) cout<<fixed<<setprecision(x)
#define forn(i,a,b) for(int i=a;i<b;i++)
#define fore(i,a,b) for(int i=a;i<=b;i++)
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define PI 3.14159265358979323846264338327
#define INF 0x3f3f3f3f
#define MOD 998244353
#define pqueue priority_queue
#define fbo find_by_order
#define ook order_of_key
typedef long long ll;
typedef pair<ll,ll> ii;
typedef vector<ll> vi;
typedef vector<ii> vii;
typedef unsigned long long ull;
typedef tree<ll, null_type, less<ll>, rb_tree_tag, tree_order_statistics_node_update> pbds;
#define MAXN 1005
int n,q;
ll h[MAXN],a[MAXN],b[MAXN];
ll dp[MAXN][MAXN];
int main()
{
ios_base::sync_with_stdio(0); cin.tie(0);
mset(dp,-1);
cin>>n;
forn(i,0,n){
cin>>h[i]>>a[i]>>b[i];
}
forn(d,1,n){
forn(i,0,n-d){
int j=i+d;
dp[i][j]=max(dp[i+1][j],dp[i][j-1]);
if(a[i]<=d && d<=b[i] && a[j]<=d && d<=b[j]){
dp[i][j]=max(dp[i][j],abs(h[i]-h[j]));
}
}
}
cin>>q;
forn(it,0,q){
int s,e; cin>>s>>e; s--; e--;
cout<<dp[s][e]<<'\n';
}
return 0;
}
