#include <bits/stdc++.h>
using namespace std;
#define int long long
#define fi first
#define se second
#define pii pair<int, int>
const int maxn = 2e5 + 5;
int a[maxn], b[maxn], pre[19][maxn];
pii st[19][maxn];
void solve(){
int n, q; cin >> n >> q;
vector<int> compress;
for (int i = 1; i <= n; i++){
cin >> a[i] >> b[i];
compress.push_back(a[i]);
compress.push_back(b[i]);
}
sort(compress.begin(), compress.end());
compress.resize(unique(compress.begin(), compress.end()) - compress.begin());
for (int i = 0; i < 19; i++){
for (int j = 1; j <= compress.size(); j++){
st[i][j] = {1e18, 1e18};
}
}
for (int i = 1; i <= n; i++){
a[i] = lower_bound(compress.begin(), compress.end(), a[i]) - compress.begin() + 1,
b[i] = lower_bound(compress.begin(), compress.end(), b[i]) - compress.begin() + 1,
st[0][b[i]] = min(st[0][b[i]], {a[i], i});
}
for (int i = 1; i < 19; i++){
for (int j = 1; j + (1 << i) - 1 <= compress.size(); j++){
st[i][j] = min(st[i - 1][j], st[i - 1][j + (1 << (i - 1))]);
}
}
for (int i = n; i >= 1; i--){
int k = __lg(b[i] - a[i] + 1);
pre[0][i] = min(st[k][a[i]], st[k][b[i] - (1 << k) + 1]).se;
}
for (int i = 1; i < 19; i++){
for (int j = 1; j <= n; j++) pre[i][j] = pre[i - 1][pre[i - 1][j]];
}
while(q--){
int u, v; cin >> u >> v;
if (u == v) cout << 0 << "\n";
else if (b[u] > b[v]) cout << "impossible\n";
else if (a[v] <= b[u] && b[u] <= b[v]) cout << 1 << "\n";
else{
int ans = 0;
int cur = v;
for (int j = 18; j >= 0; j--){
if (a[pre[j][cur]] > b[u]){
ans += 1 << j;
cur = pre[j][cur];
}
}
if (a[pre[0][cur]] <= b[u]) cout << ans + 2 << "\n";
else cout << "impossible\n";
}
}
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
solve();
}
