Which of the following belong to the profit model of B2C e-commerce?
A. Merchant sales commission.
B. Offline service charges for training, exhibitions, forums, etc.
C. Price difference between products or services.
D. Sales profit of agents.
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From the following answer choices, which one is not part of the service phase of the basic logistics activities?
A. Delivery
B. Customer service
C. Return processing
D. Waste disposal
All of the following statements about public key encryption are true except ________.
A. public key encryption uses two mathematically related digital keys.
B. public key encryption ensures authentication of the sender.
C. public key encryption does not ensure message integrity.
D. public key encryption is based on the idea of irreversible mathematical functions.
Which of the following institutions can issue digital certificate?
A. Windows Server
B. CA
C. RA
D. PKI
________ belongs to the satellite communication system.
A. Satellite
B. Roaming end
C. Ground station
D. Client
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