The Mountain amusement ride has the following system of internal control over cash receipts. All persons pay the same price for a ride. A person taking the ride pays cash to the cashier and receives a prenumbered ticket. The tickets are issued in strict number sequence. The individual then walks to the ride site, hands the ticket to a ticket-taker (who controls the number of people getting on each ride), and passes through a turnstile. At the end of each day, the beginning ticket number is subtracted from the ending ticket number to determine the number of tickets sold. The cash is counted and compared with the number of tickets sold. The turnstile records how many people pass through it. At the end of each day, the beginning turnstile count is subtracted from the ending count to determine the number of riders that day. The number of riders is compared with the number of tickets sold.

Required 

Which internal control feature would reveal each of the following irregularities?

a. The ticket-taker lets her friends on the ride without tickets.

b. The cashier gives his friends tickets without receiving cash from them.

c. The cashier gives too much change.

d. The ticket-taker returns the tickets she has collected to the cashier. The cashier then resells these tickets and splits the proceeds with the ticket-taker.

e. A person sneaks into the ride line without paying the cashier.