Read the following text and answer the questions that follow. (Items 26-70) What do the numbers given in the table refer to?
• We can usually hear sounds of not less than 25 decibels.
• Normal conversation ranges between 55-60 decibels.
• A drumbeat gives out sounds of around 90 decibels, which people cannot ordinarily cope with for more than eight hours.
• We can only stand noises of between 100-120 decibels for about 15 minutes, after which our nervous system can be seriously impacted. (Close-up aeroplanes and loud discos both come within this category.)
• Sounds greater than 90 decibels are dangerous for our health.