1. Which of the following statements about calling-card or credit-card calls is true?
A. Calling-and credit-card are also referred to as "0+" or "0-" calls.
B. Calling cards are issued by the hotels to their guests.
C. Guests making calls using calling cards or credit cards cannot direct-dial those calls.
D. A and C
2. Which of the following is an advantage of a digital trunk line over an analog trunk line?
A. Digital trunk provide greater reliability.
B. Digital trunk provide faster connections.
C. Digital trunks can carry several conversations at the same time.
D. All of the above
3. A long-distance carrier that does not own its own telephone network is called a(n):
A. Aggregator
B. Nationwide common carrier.
C. Operator-service provider.
D. Regional carrier.