#include <bits/stdc++.h>
#define fi first
#define se second
#define FOR(i, a, b) for (int i = a, _b = b; i <= _b; ++i)
#define FORD(i, a, b) for (int i = a, _b = b; i >= _b; --i)
#define FORLL(i, a, b) for (ll i = a, _b = b; i <= _b; ++i)
#define FORDLL(i, a, b) for (ll i = a, _b = b; i >= _b; --i)
#define all(x) x.begin(), x.end()
#define uni(x) sort(all(x)), x.erase(unique(all(x)), x.end())
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define dbg(...) debug(#__VA_ARGS__, __VA_ARGS__)
template<typename T>
void __prine_one(const char *&s, const T &x)
{
while (*s == ' ') ++s;
const char *p = s;
int bal = 0;
while (*s)
{
if (*s == '(') ++bal;
else if (*s == ')') --bal;
else if (*s == ',' && bal == 0) break;
++s;
}
cerr.write(p, s - p) << " = " << x;
if (*s == ',')
{
cerr << " , ";
++s;
}
}
template<typename... Args>
void debug(const char *s, Args... args)
{
cerr << "[ ";
int dummy[] = {0, (__prine_one(s, args), 0)...};
(void)dummy;
cerr << " ]\n\n";
}
// --------------------------------------------------------------------------------------------
const int maxn = 1e5 + 3;
int n, POS[maxn], q, m;
struct Segment
{
int s, e;
bool operator == (const Segment &other) const
{
return s == other.s && e == other.e;
}
bool operator < (const Segment &other) const
{
if (s == other.s) return e < other.e;
return s < other.s;
}
} a[maxn];
vector<Segment> S;
pii seg[maxn << 3], nx[maxn][20];
vector<int> ids;
// --------------------------------------------------------------------------------------------
void upd(int id, int l, int r, int pos, pii val)
{
if (l == r)
{
seg[id] = min(seg[id], val);
return;
}
int mid = l + r >> 1;
if (pos <= mid) upd(id << 1, l, mid, pos, val);
else upd(id << 1 | 1, mid + 1, r, pos, val);
seg[id] = min(seg[id << 1], seg[id << 1 | 1]);
}
pii get(int id, int l, int r, int u, int v)
{
if (l > v || r < u) return {(int)1e9, (int)1e9};
if (l >= u && r <= v) return seg[id];
int mid = l + r >> 1;
return min(get(id << 1, l, mid, u, v), get(id << 1 | 1, mid + 1, r, u, v));
}
void process()
{
int u, v; cin >> u >> v;
if (u == v)
return void(cout << "0\n");
u = POS[u];
v = POS[v];
if (S[v].e < S[u].e)
return void(cout << "impossible\n");
if (S[u].e >= S[v].s && S[u].e <= S[v].e)
return void(cout << "1\n");
int res = 0;
FORD(i, 19, 0)
{
int cur_nx = nx[v][i].se;
if (cur_nx == 1e9 || S[cur_nx].s <= S[u].e)
continue;
res += 1 << i;
v = cur_nx;
}
if (nx[v][0].se == 1e9 || S[nx[v][0].se].s > S[u].e)
return void(cout << "impossible\n");
v = nx[v][0].se;
++res;
res += u != v;
cout << res << '\n';
}
void solve()
{
cin >> n >> q;
S.push_back({0, 0});
FOR(i, 1, n)
{
cin >> a[i].s >> a[i].e;
S.push_back({a[i].s, a[i].e});
ids.push_back(a[i].s);
ids.push_back(a[i].e);
}
uni(S);
uni(ids);
// for (const auto &e : S)
// dbg(e.s, e.e);
FOR(i, 1, n)
{
POS[i] = lower_bound(all(S), a[i]) - S.begin();
}
m = (int)S.size() - 1;
FOR(i, 1, m)
{
auto &e = S[i];
e.s = lower_bound(all(ids), e.s) - ids.begin() + 1;
e.e = lower_bound(all(ids), e.e) - ids.begin() + 1;
}
FOR(i, 1, (int)ids.size() << 2)
seg[i] = {(int)1e9, (int)1e9};
FOR(i, 1, m)
{
pii cur = get(1, 1, (int)ids.size(), S[i].s, S[i].e);
nx[i][0] = cur;
upd(1, 1, (int)ids.size(), S[i].e, pii(S[i].s, i));
}
FOR(j, 1, 19)
FOR(i, 1, m)
{
nx[i][j] = nx[i][j - 1];
if (nx[i][j - 1].se != 1e9)
nx[i][j] = min(nx[i][j - 1], nx[nx[i][j - 1].se][j - 1]);
}
while (q--)
{
process();
}
}
signed main()
{
ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define TASK "TEST"
if (fopen(TASK".INP", "r"))
{
freopen(TASK".INP", "r", stdin);
freopen(TASK".OUT", "w", stdout);
}
solve();
return 0;
}
