Students Arrive Randomly at the Help Desk of the Computer

question 112

Multiple Choice

Students arrive randomly at the help desk of the computer lab. There is only one service agent, and the time required for inquiry varies from student to student. Arrival rates have been found to follow the Poisson distribution, and the service times follow the negative exponential distribution. The average arrival rate is 12 students per hour, and the average service rate is 20 students per hour. A student has just entered the system. How long is she expected to stay in the system?

• A) 0.125 minute
• B) 0.9 minute
• C) 1.5 minutes
• D) 7.5 minutes
• E) 0.075 hour

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Definitions:

Motor Tasks

Activities that require movement and coordination of muscles and limbs.

Amygdala

A part of the brain located in the temporal lobe, involved in emotion regulation, memory processing, and decision-making, particularly with responses to fear and pleasure.

Cerebral Cortex

A collection of several thin layers of cells covering the cerebrum; it is largely responsible for higher mental functions. Cortex is Latin for “bark” or “rind.”

Medulla

A structure in the brain stem responsible for certain automatic functions, such as breathing and heart rate.