const
  maxn=1000000007;
var
  cas,xx,n,i:longint;
  ans:int64;
  a,b,st,ed,shit,num,x,y:array[0..300010]of longint;
  mi:array[0..200010]of int64;
  procedure qsort(l,r:longint);
    var
      i,j,mid,p:longint;
      begin
        i:=l; j:=r; mid:=a[(l+r) div 2];
        repeat
          while a[i]<mid do inc(i);
          while a[j]>mid do dec(j);
          if i<=j then
            begin
              p:=a[i]; a[i]:=a[j]; a[j]:=p;
              p:=b[i]; b[i]:=b[j]; b[j]:=p;
              inc(i); dec(j);
            end;
        until i>j;
        if l<j then qsort(l,j);
        if i<r then qsort(i,r);
      end;
  begin
    mi[0]:=1;
    for i:=1 to 100000 do mi[i]:=mi[i-1]*2 mod maxn;
    readln(cas);
    for xx:=1 to cas do
      begin
        readln(n);
        for i:=1 to n do
          begin
            readln(x[i],y[i]);
            a[i*2-1]:=x[i];
            b[i*2-1]:=i*2-1;
            a[i*2]:=y[i];
            b[i*2]:=i*2;
          end;
        qsort(1,2*n);
        for i:=1 to 2*n do
          begin
            if odd(b[i]) then st[(b[i]+1) div 2]:=i
              else ed[b[i] div 2]:=i;
            num[i]:=a[i+1]-a[i];
          end;
        fillchar(shit,sizeof(shit),0);
        for i:=1 to n do
          begin
            inc(shit[st[i]]);
            dec(shit[ed[i]]);
          end;
        ans:=0;
        for i:=1 to 2*n do
          begin
            shit[i]:=shit[i]+shit[i-1];
            if i<>2*n then ans:=(ans+(mi[n]-mi[n-shit[i]]+maxn) mod maxn*num[i]) mod maxn;
          end;
        writeln(ans);
      end;
  end.