#include <iostream>
#include <vector>
#include <map>
using namespace std;
int n, q, mx, nxt, A, B, a, b, ans;
vector <int> s(3e5, 0);
vector <int> e(3e5, 0);
map<int, int> cc;
vector <int> L(3e5, 3e5);
vector <int> l(3e5, 3e5);
vector <vector <int>> r(3e5, vector <int>(20, 0));
int lift() {
int ret = 0;
for (int j = 19; j >= 0; j--) {
if (r[a][j] >= b) continue;
a = r[a][j];
ret += (1 << j);
}
return ret;
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin >> n >> q;
for (int i = 1; i <= n; i++) {
cin >> s[i] >> e[i];
cc[s[i]] = cc[e[i]] = 0;
}
nxt = 0;
for (auto p : cc) cc[p.first] = nxt++;
for (int i = 1; i <= n; i++) {
s[i] = cc[s[i]];
e[i] = cc[e[i]];
mx = max(mx, e[i]);
}
for (int i = 0; i <= mx; i++) L[i] = i;
for (int i = 1; i <= n; i++) L[e[i]] = min(L[e[i]], s[i]);
l = L;
for (int i = mx - 1; i >= 0; i--) l[i] = min(l[i], l[i + 1]);
nxt = 0;
for (int i = 0; i <= mx; i++) {
while (l[nxt] <= i) nxt++;
r[i][0] = nxt - 1;
}
for (int j = 1; j < 20; j++) {
for (int i = 0; i <= mx; i++) {
r[i][j] = r[r[i][j - 1]][j - 1];
}
}
/*cout << endl << endl;
for (int i = 0; i <= mx; i++) cout << l[i] << " ";
cout << endl << endl;
for (int i = 0; i <= mx; i++) cout << r[i][0] << " ";
cout << endl << endl;
for (int j = 0; j < 4; j++) {
cout << endl;
for (int i = 0; i <= mx; i++) {
cout << r[i][j] << " ";
}
}
cout << endl << endl;*/
for (int i = 0; i < q; i++) {
cin >> A >> B;
if (A == B) { cout << "0\n"; continue; }
if (e[A] == e[B]) { cout << "1\n"; continue; }
if (e[A] > e[B]) { cout << "impossible\n"; continue; }
a = e[A]; b = e[B];
ans = lift();
if (a < L[e[B]]) { cout << "impossible\n"; continue; }
if (a < s[B]) { cout << ans + 2 << "\n"; continue; }
cout << ans + 1 << "\n";
}
}
