#include<cstdio>
#include<iostream>
#include<cmath>
#include<map>
#include<cassert>
#define RI register int
#define CI const int&
using namespace std;
const int N=1000000;
const double alpha=pow(2.0,2.0/3.0);
const double theta=alpha/(1.0+alpha);
int t,n,cnt,f[N+5],pos[N+5]; map <pair <int,int>,int> rst;
inline int ask(CI l,CI r)
{
    if (rst.count({l,r})) return rst[{l,r}];
    printf("? %d %d\n",l,r); fflush(stdout); ++cnt;
    int res; scanf("%d",&res); return rst[{l,r}]=res;
}
inline void answer(CI p)
{
    printf("! %d\n",p); fflush(stdout);
}
int main()
{
    f[1]=0; f[2]=1;
    for (RI i=3;i<=N;++i)
    {
        int st=max(1,(int)(theta*i)-1);
        pos[i]=st; f[i]=max(f[st],f[i-st]+1)+1;
        for (RI j=1;j<=3;++j)
        {
            int y=min(st+j,i-1);
            int tmp=max(f[y],f[i-y]+1)+1;
            if (tmp<f[i]) f[i]=tmp,pos[i]=y;
        }
    }
    //for (RI i=1;i<=N;++i) assert(f[i]<=(int)ceil(1.5L*log2(i)));
    for (scanf("%d",&t);t;--t)
    {
        scanf("%d",&n); rst.clear(); cnt=0;
        int l=1,r=n;
        while (r-l+1>2)
        {
            int smx=ask(l,r),len=pos[r-l+1];
            if (smx<=l+len-1)
            {
                int tmp=ask(l,l+len-1);
                if (smx==tmp) r=l+len-1; else l+=len;
            } else
            {
                int tmp=ask(r-len+1,r);
                if (smx==tmp) l=r-len+1; else r-=len;
            }
        }
        if (l==r) answer(l); else
        {
            int tmp=ask(l,r);
            if (tmp==l) answer(r); else answer(l);
        }
        assert(cnt<=(int)ceil(1.5L*log2(n)));
    }
    return 0;
}