#include<bits/stdc++.h>
#define ll long long
#define P make_pair
using namespace std;
int n;
const double k = 0.629;
int ask(int l, int r) {
    if(l == r) return -1;
    cout << "? " << l << ' ' << r << endl;
    int x;
    cin >> x;
    return x;
}
void answer(int x) {
    cout << "! " << x << endl;
    return;
}
pair<int,ll> f[1000001];
int deg[1000001];
void solve(int l, int r, int sec = -1) {
    if(l == r) {
        answer(l);
        return;
    }
    if(sec == -1) sec = ask(l, r);
    if(l + 1 == r) {
        answer(l == sec ? r : l);
        return;
    }
    int mid = deg[r-l+1];
    if(l + mid - 1 >= sec) {
        mid = l + mid - 1;
        int u = ask(l, mid);
        if(u == sec) {
            return solve(l, mid, sec);
        } else return solve(mid + 1, r, -1);
    } else {
        mid = r - mid + 1;
        int u = ask(mid, r);
        if(u == sec) {
            return solve(mid, r, sec);
        } else return solve(l, mid - 1, -1);
    }
}
void init()
{
    int mx=0;
    memset(f,0x3f,sizeof(f));
    f[1]=P(0,0);
    f[2]=P(0,0),deg[2]=1;
    for(int i=3;i<=1000000;++i)
    {
        if(i<=1000)
        for(int j=i/2;j<=i;++j)
        {
            if(f[i]>max(P(f[j].first+1,f[j].second+j),P(f[i-j].first+2,f[i-j].second+i)))
            {
                f[i]=max(P(f[j].first+1,f[j].second+j),P(f[i-j].first+2,f[i-j].second+i));
                deg[i]=j;
            }
        }
        else
        {
            for(int j=i*k-100;j<=i*k+100;++j)
            if(f[i]>max(P(f[j].first+1,f[j].second+j),P(f[i-j].first+2,f[i-j].second+i)))
            {
                f[i]=max(P(f[j].first+1,f[j].second+j),P(f[i-j].first+2,f[i-j].second+i));
                deg[i]=j;
            }
        }
        // if(f[i].first+1>ceil(1.5*log2(i))||f[i].second>2*i)
        // {
        //     cout<<i<<" "<<ceill((long double)1.5*log2l(i))<<" "<<f[i].first+1<<" "<<f[i].second<<endl;
        //     exit(0);
        // }    
    }
}
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int T;
    cin >> T;
    init();
    while(T--) {
        int n;
        cin >> n;
        solve(1, n);
    }
}