#include <bits/stdc++.h>
using namespace std;
#define int long long
#define all(x) x.begin(), x.end()
#define tp3 tuple<int, int, int>
const int N = 1e6, L = 17 + 10;
int n, q, dp[L][N], ans[N];
pair<int, int> sg[N];
tp3 sgL[N], sgR[N];
signed main() {
ios::sync_with_stdio(false); cin.tie(nullptr);
cin >> n >> q;
for (int i = 0; i < n; i++) {
int l, r;
cin >> l >> r;
sg[i] = make_pair(l, r);
sgL[i] = make_tuple(l, r, i);
sgR[i] = make_tuple(r, l, i);
}
sort(sgL, sgL+n);
sort(sgR, sgR+n);
int curr = 0;
int mx = -1;
int mxIdx = -1;
for (int i = 0; i < n; i++) {
int r = get<0>(sgR[i]);
int idx = get<2>(sgR[i]);
while (curr < n && get<0>(sgL[curr]) <= r) {
int nwMx = get<1>(sgL[curr]);
if (nwMx > mx) {
mx = nwMx;
mxIdx = get<2>(sgL[curr]);
}
curr++;
}
if (mx >= r) {
if (mx == r) dp[0][idx] = idx;
else dp[0][idx] = mxIdx;
}
else dp[0][idx] = -1;
//cerr << idx+1 << " " << dp[0][idx]+1 << endl;
}//cerr << endl;
for (int j = 1; j < L; j++) {
for (int i = 0; i < n; i++) {
dp[j][i] = dp[j-1][dp[j-1][i]];
}
}
vector<tp3> queries;
for (int i = 0; i < q; i++) {
int x, y;
cin >> x >> y;
x--; y--;
if (sg[y].second < sg[x].second) {
//cerr << "-1 " << i << endl;
ans[i] = -1;
}
else if (x == y) {
//cerr << "0 " << i << endl;
ans[i] = 0;
}
else if (sg[y].first <= sg[x].second && sg[x].second <= sg[y].second) {
//cerr << "1 " << i << endl;
ans[i] = 1;
}
else {
//cerr << "2 " << i << endl;
// ir a la r maxima que sea < sg[y].first
int cnt = 0;
int z = x;
for (int j = L-1; j >= 0; j--) {
if (dp[j][z] == -1 || sg[dp[j][z]].second >= sg[y].first || dp[j][z] == z || (j && dp[j-1][z] == dp[j][z])) continue;
cnt += (1 << j);
z = dp[j][z];
}
//cerr << cnt << " " << z+1 << endl;
ans[i] = cnt;
queries.push_back(make_tuple(sg[z].second, y, i));
}
}
sort(all(queries));
curr = 0;
set<int> rs;
for (auto& [r, y, idx] : queries) {
while (curr < n && get<0>(sgL[curr]) <= r) {
rs.insert(get<1>(sgL[curr]));
curr++;
}
auto it = rs.lower_bound(sg[y].first);
if (it != rs.end() && *it <= sg[y].second) {
ans[idx] += 2;
}
else {
ans[idx] = -1;
}
}
for (int i = 0; i < q; i++) {
if (ans[i] == -1) cout << "impossible\n";
else cout << ans[i] << "\n";
}
}
