# 455 Aug 25

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# Did not use these questions on 8/25. Moved back to 8/27.
# Review

If a certain event occurs every 20milliseconds (ms) then how many times does it occur each second?
  20
  200
  5000
  500
  50

Network speeds are often described in terms such as Mbit/s, Kbit/s, Gbit/s. If a network's speed is given as 10 Mbit/s how long does it take to send 1000 bits?
  100 milliseconds
  1000 milliseconds
  1000 microseconds
  100 microseconds
  0.1 milliseconds

# New

What is the usual cause of queueing delay in packet switched networks?
  More than one packet is ready to be sent on a link at a given time
  Links break down and can't be used for awhile
  Packets have to traverse multiple links to get to their destination
  Some packets are more important than other packets and go to the head of the line