If the number of customers in a queue is 8, the arrival rate is 2 ...

[Charlie]

If the number of customers in a queue is 8, the arrival rate is 2 customers per minute, and the customer service rate is 4 customers per minute, what is the average number of customers in the system?
 
  A) 10 customers
  B) 12 customers
  C) 8.5 customers
  D) 10.5 customers

Question 2

Stratified random sampling ________.
 
  A) eliminates homogeneous sampling error
  B) is used with populations that are naturally divided into subsets
  C) has the drawback of introducing sampling bias
  D) allocates sampling error disproportionately

[Moriaki]

Answer to Question 1

C

Answer to Question 2

B