In simple terms, DHCP determines if your IP is static or dynamic and the length of time an IP address is assigned. Dynamic Host Configuration Protocol is controlled by a DHCP server. Your router can be a DHCP server...and if you're on a home network, it most likely serves this purpose.
Researchers report that the average adolescent needs eight and a half to nine and a half hours of sleep each night. But in a poll taken in 2006 by the National Sleep Foundation, less than 20 percent reported getting that much rest on school nights.
Those who slept for fewer than seven hours a night had more sickness. The lead author, Kathryn Orzech, says research shows that teenagers need 9.5 hours sleep a night, but on average get only 7.5 hours. But this doesn't mean that it is normal for teenagers not to get enough sleep, says Orzech.