#include <bits/stdc++.h>
#define ll long long
#define pii pair <ll, ll>
#define st first
#define nd second
#define rep(i, n, m) for (ll i = (n); i <= (m); i ++)
#define rrep(i, n, m) for (ll i = (n); i >= (m); i --)
using namespace std;
const long long INF = 1e18;
const long long N = 1e5 + 5;
ll n, q, s[N], e[N];
vector <int> cmp, out[2 * N], in[2 * N];
vector <int> d[N];
const ll Nmax = 5005;
int dist[Nmax][Nmax];
void bfs(int st, int *f) {
rep(i, 1, n) f[i] = 1e9;
f[st] = 0;
queue <int> q;
q.push(st);
while (q.size()) {
int u = q.front(); q.pop();
for (int v: d[u]) if (f[v] > f[u] + 1) {
f[v] = f[u] + 1;
q.push(v);
}
}
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> n >> q;
rep(i, 1, n) {
cin >> s[i] >> e[i];
cmp.push_back(s[i]);
cmp.push_back(e[i]);
}
sort(cmp.begin(), cmp.end());
cmp.resize(unique(cmp.begin(), cmp.end()) - cmp.begin());
auto find = [&] (ll x) {
return lower_bound(cmp.begin(), cmp.end(), x) - cmp.begin() + 1;
};
rep(i, 1, n) {
s[i] = find(s[i]);
e[i] = find(e[i]);
in[s[i]].push_back(i);
out[e[i]].push_back(i);
}
set <int> save;
rep(timer, 1, 2 * n) {
for (int i: in[timer]) save.insert(i);
for (int i: out[timer]) {
for (int j: save)
d[i].push_back(j);
}
for (int i: out[timer])
save.erase(i);
}
rep(i, 1, n) bfs(i, dist[i]);
while (q --) {
int u, v;
cin >> u >> v;
if (dist[u][v] >= (int)1e9)
cout << "impossible\n";
else
cout << dist[u][v] << '\n';
}
return 0;
}
