#include <iostream>
#include <algorithm>
#include <functional>
#include <random>
#include <cmath>
#include <vector>
#include <array>
#include <set>
#include <map>
#include <queue>
#include <cassert>
#include <string>
#include <bitset>
#include <numeric>
#include <iomanip>
#include <limits.h>
#include <tuple>
// #pragma GCC optimization ("unroll-loops")
// #pragma GCC optimization ("O3")
// #pragma GCC target ("avx2")
using namespace std;
typedef long long ll;
typedef pair<int, int> pp;
#define per(i,r,l) for(int i = (r); i >= (l); i--)
#define rep(i,l,r) for(int i = (l); i < (r); i++)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
#define pb push_back
#define ss second
#define ff first
//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const ll mod = 1e9 + 7, maxn = 5e5 + 5, lg = 25, inf = ll(1e9) + 5;
ll pw(ll a,ll b,ll md=mod){if(!b)return 1;ll k=pw(a,b>>1ll);return k*k%md*(b&1ll?a:1)%md;}
pp seg[maxn<<2];
void upd(int i, pp k, int x = 1, int lx = 0, int rx = maxn){
if(lx + 1 == rx) {
seg[x] = min(seg[x], k);
return;
}
int mid = (lx + rx)>>1;
if(i < mid) upd(i, k, x<<1, lx, mid);
else upd(i, k, x<<1|1, mid, rx);
seg[x] = min(seg[x<<1], seg[x<<1|1]);
}
pp get(int l, int r, int x = 1, int lx = 0, int rx = maxn){
if(l <= lx && r >= rx) return seg[x];
int mid = (lx + rx)>>1;
pp res = {inf, inf};
if(l < mid) res = get(l, r, x<<1, lx, mid);
if(mid < r) res = min(res, get(l, r, x<<1|1, mid, rx));
return res;
}
int nxt[maxn][lg];
int main(){
cin.tie(0) -> sync_with_stdio(0);
int n, q; cin >> n >> q;
rep(i,0,maxn<<2) seg[i] = {inf, inf};
map<int, int> comp;
vector<pp> trk(n);
rep(i,0,n) cin >> trk[i].ss >> trk[i].ff, comp[trk[i].ff] = comp[trk[i].ss] = 0;
vector<int> id(n), inv(n); iota(all(id), 0), sort(all(id), [&](int i, int j){ return trk[i] < trk[j]; });
rep(i,0,n) inv[id[i]] = i;
int dd = 0;
for(auto&c:comp) c.ss = dd++;
assert(dd < maxn);
rep(i,0,n){
auto[r, l] = trk[id[i]];
upd(comp[r], {l, i});
nxt[i][0] = get(comp[l], comp[r]+1).ss;
rep(j,1,lg) nxt[i][j] = nxt[nxt[i][j-1]][j-1];
assert(nxt[i][0] < n);
}
while(q--){
int l, r; cin >> l >> r; l = inv[--l], r = inv[--r];
if(l == r) cout << 0 << '\n';
else if(l > r) cout << "impossible\n";
else{
auto chk = [&](int i, int j){
return trk[id[i]].ff >= trk[id[j]].ss;
};
if(chk(l, r)) {
cout << 1 << '\n';
continue;
}
int ans = 0;
per(i,lg-1,0) if(!chk(l, nxt[r][i])) r = nxt[r][i], ans |= 1<<i;
if(!chk(l, nxt[r][0])) cout << "impossible\n";
else if(chk(l, r)) cout << ans + 1 << '\n';
else cout << ans + 2 << '\n';
}
}
return 0;
}
