An electric utility tracks the response time to

customer reported outages.

The data in Table $8$E$.7$ are a random sample

of $40$ of the response times $($in minutes$)$ for

one operating division of this utility during a

single month.

The utility wants to achieve a response rate

in under two hours, as response to

emergency outages is an important measure

of customer satisfaction.

a$)$ What is the capability of the process with

respect to this objective?

TABLE $8$E$.7$

Response Time Data

b$)$ What proportion of customers will wait

longer then two$-$hours?

c$)$ What are the natural tolerance limits$?$