#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> v;
typedef vector<v> vv;
typedef vector<vv> vvv;
typedef pair<ll, ll> p;
typedef vector<p> vp;
typedef vector<vp> vvp;
typedef vector<vvp> vvvp;
typedef pair<ll, p> tri;
typedef vector<tri> vtri;
typedef vector<vtri> vvtri;
typedef vector<vvtri> vvvtri;
typedef vector<bool> vb;
typedef vector<vb> vvb;
typedef vector<vvb> vvvb;
#define f first
#define s second
#define pb push_back
#define eb emplace_back
#define all(v) (v).begin(),(v).end()
const ll INF = 1e18;
const ll mod = 1e9 + 7;
int main()
{
ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
ll N, Q;
cin >> N >> Q;
vp events(N);
for (ll i = 0; i < N; i++) cin >> events[i].f >> events[i].s;
v prev(N);
for (ll curEvent = 0; curEvent < N; curEvent++)
{
ll earliestStart = events[curEvent].f;
ll bestEvent = curEvent;
for (ll i = 0; i < N; i++)
{
if (events[i].s >= events[curEvent].f && events[i].s <= events[curEvent].s)
{
if (events[i].f < earliestStart)
{
earliestStart = events[i].f;
bestEvent = i;
}
}
}
prev[curEvent] = bestEvent;
}
ll logN = log2(N);
vv prevLifting(N, v(logN + 1, -1));
for (ll i = 0; i < N; i++) prevLifting[i][0] = prev[i];
for (ll j = 1; j <= logN; j++)
{
for (ll i = 0; i < N; i++)
{
prevLifting[i][j] = prevLifting[prevLifting[i][j - 1]][j - 1];
}
}
while (Q--)
{
ll s, e;
cin >> s >> e; s--; e--;
if (s == e)
{
cout << "0\n";
continue;
}
if (events[s].s > events[e].s)
{
cout << "impossible\n";
continue;
}
if (events[e].f <= events[s].s && events[e].s >= events[s].s)
{
cout << "1\n";
continue;
}
ll curEvent = e;
ll hops = 0;
for (ll j = logN; j >= 0; j--)
{
ll next = prevLifting[curEvent][j];
if (events[s].s < events[next].f)
{
curEvent = next;
hops += (1 << j);
}
}
curEvent = prev[curEvent]; hops++;
if (events[s].s >= events[curEvent].f)
{
cout << hops + 1 << "\n";
continue;
}
cout << "impossible\n";
}
return 0;
}
