Question $1(1$ point$)$

Which probability distribution is commonly used to describe customer arrivals per unit of time $($eg$,$ per hour$)$ in waiting line theory?

Normal distribution

Bernoulli distribution

Exponential distribution

Poisson distribution

Question $2(1$ point$)$

When arrivals at a service facility are bunched or service times are lengthy, what is likely to occur?

Increase in the number of servers

Decrease in service variability

Formation or increase in the length of waiting lines

Reduction in waiting times