题目

       Learn to relax. Overwork is the main reason why so many students feel tired and stressed(紧张). Cut down some of the jobs you need to do each day so that you can only focus on the most important things. Leave time for activities that are relaxing and fun. This might mean reading a good book, listening to the music, going for a walk or taking a relaxing bath.        Get a good night’s sleep. Getting enough sleep will help you keep your body and mind in the best form. If you stay up late and need to get up early for school the next day, you may not be able to conce把一个正方形的周长放大到原来的3倍，则原图形与新图的相似比为    ．