The questions in this Hard Chapter Test are as difficult as any that appear on the GMAT. So, at this stage of your preparation, it does not make sense to seek answer them in under two minutes.
Rather, for best results, you should hide the timer and answer these questions untimed, taking as much time as you need to fully understand and analyze each question.
By practicing in this way, you will give yourself time to learn to see what’s going on in the questions and to learn to work your way to correct answers to difficult questions.