Вопрос по английскому языку:

Choose the variant. 1) Who is THE TALLEST/TALLEST/TALLER student in your class? 2) The Thames is as LONG/LONGER/THE LONGER as the Volga , isn't it? 3) You should be MORE ATTENTIVE/ ATTENTIVELIER/MOST ATTENTIVE at the lessons. 4) Travelling by plane is MUCH MORE COMFORTABLE /MOST COMFORTABLE/MUCH COMFORTABLE for me than travelling by bus.