Counter$($s$)$

Activity Time

Wage per Person per

A

$10$ secs$.$

Hour

B

$30$ secs$.$

$$6$

C

$60$ secs$.$

$7$

D

$40$ secs$.$

$7$

E

$30$ secs$.$

$7$

F

$20$ secs$.$

$8$

Refer to Exhibit $5-1.$ How many customers can this cafeteria process in an hour?

$90$

$360$

$120$

$180$

$240$