#include<bits/stdc++.h>
using namespace std;
const int MAXN = 2005;
int n, q;
int h[MAXN], a[MAXN], b[MAXN];
int cost[MAXN][MAXN], dp[MAXN][MAXN], res[MAXN][MAXN];
void precompute () {
memset(cost, -1, sizeof cost);
memset(dp, -1, sizeof dp);
memset(res, -1, sizeof res);
for (int i = 1; i <= n; i++) {
for (int j = i + 1; j <= n; j++) {
if (a[i] <= j - i && j - i <= b[i] && a[j] <= j - i && j - i <= b[j]) {
cost[i][j] = abs(h[i] - h[j]);
}
dp[i][j] = max(dp[i][j - 1], cost[i][j]);
}
}
for (int rig = 1; rig <= n; rig++) {
for (int lef = rig - 1; lef >= 1; lef--) {
res[lef][rig] = max(res[lef + 1][rig], dp[lef][rig]);
}
}
}
int main () {
ios_base::sync_with_stdio(false);
cin.tie(0);
cin >> n;
if (n > 2000) return 0;
for (int i = 1; i <= n; i++) {
cin >> h[i] >> a[i] >> b[i];
}
precompute();
cin >> q;
for (int i = 0; i < q; i++) {
int lef, rig;
cin >> lef >> rig;
cout << res[lef][rig] << '\n';
}
return 0;
}
