$1.$ The process of comparing a Simio model to its underlying mathematical model to make sure it implemented correctly is called:

a$)$ verification

b$)$ validation

c$)$ simulation

d$)$ experimentation

e$)$ None of the above

$2.$ The number of entities exiting a system at any given time is referred to as:

a$)$ W

b$)$ Wq

c$)$ L

d$)$ Lq

e$)$ None of the above

$3.$ If the service rate is changed from $6/$min to $5/$min while the arrival rate remains constant and all other factors remain unchanged, then, in general:

a$)$ the service queue increases

b$)$ the service queue is unchanged

c$)$ the service queue decreases

d$)$ the effect on customer waiting time cannot be determined

e$)$ any of the above might be the case