#include <bits/stdc++.h>
using namespace std;
const int MAXN = 2e5 + 2;
const int OFF = 1 << 19;
const int LOG = 17;
int n, q, s[MAXN], e[MAXN], bl[MAXN][LOG];
set<pair<int, int> > st;
vector<pair<int, bool> > v[MAXN];
pair<int, int> tour[OFF];
void upd(int x, int l, int r, int i, pair<int, int> val, bool keep = 0){
if(i < l || i > r) return ;
if(l == r){
if(keep) tour[x] = min(tour[x], val);
else tour[x] = val;
return ;
}
int mid = (l + r) >> 1;
upd(x * 2 + 1, l, mid, i, val, keep);
upd(x * 2 + 2, mid + 1, r, i, val, keep);
tour[x] = min(tour[x * 2 + 1], tour[x * 2 + 2]);
}
pair<int, int> f(int x, int l, int r, int ql, int qr){
if(ql > r || l > qr) return {1e9, 0};
if(ql <= l && r <= qr) return tour[x];
int mid = (l + r) >> 1;
return min(f(x * 2 + 1, l, mid, ql, qr), f(x * 2 + 2, mid + 1, r, ql, qr));
}
int main(){
ios_base::sync_with_stdio(false); cin.tie(0);
cin >> n >> q;
unordered_map<int, int> um;
vector<int> cmp;
for(int i = 0; i < n; ++i){
cin >> s[i] >> e[i];
cmp.push_back(s[i]);
cmp.push_back(e[i]);
}
sort(cmp.begin(), cmp.end());
cmp.erase(unique(cmp.begin(), cmp.end()), cmp.end());
for(int i = 0; i < (int)cmp.size(); ++i){
um[cmp[i]] = i;
}
for(int i = 0; i < n; ++i){
s[i] = um[s[i]]; e[i] = um[e[i]];
v[s[i]].push_back({i, 0});
v[e[i]].push_back({i, 1});
}
for(int i = 0; i < 2 * n; ++i) upd(0, 0, 2 * n - 1, i, {1e9, 0});
for(int i = 0; i < n; ++i) upd(0, 0, 2 * n - 1, e[i], {s[i], i}, 1);
for(int i = 0; i < n; ++i){
bl[i][0] = f(0, 0, 2 * n - 1, s[i], e[i]).second;
}
for(int j = 1; j < LOG; ++j){
for(int i = 0; i < n; ++i){
bl[i][j] = bl[bl[i][j - 1]][j - 1];
}
}
while(q--){
int qs, qe; cin >> qs >> qe, --qs, --qe;
if(qs == qe){
cout << "0\n"; continue;
} else if(s[qe] <= e[qs] && e[qs] <= e[qe]){
cout << "1\n"; continue;
} else if(e[qs] > e[qe]){
cout << "impossible\n"; continue;
}
int ret = 0;
for(int i = LOG - 1; i >= 0; --i){
int idx = bl[qe][i];
if(e[qs] < s[idx]){
qe = idx;
ret += 1 << i;
}
}
if(e[qs] < s[bl[qe][0]]) cout << "impossible\n";
else cout << ret + 2;
}
return 0;
}
