To make white sugar, sulfur dioxide is added to cane juice before it gets evaporated. This gas does the bleaching of the juice so that it does not turn brown and produces white sugar. At later stages, phosphoric acid, calcium hydroxide or carbon dioxide is added to absorb impurities.
The first REM sleep period usually occurs about 70 to 90 minutes after we fall asleep. A complete sleep cycle takes 90 to 110 minutes on average. The first sleep cycles each night contain relatively short REM periods and long periods of deep sleep.
Sleep Deprivation Sleep deprivation occurs when an individual fails to get enough sleep. The amount of sleep that a person needs varies from one person to another, but on average most adults need about seven to eight hours of sleep each night to feel alert and well rested. Teens need an average of about nine hours of sleep per night, and children