b. storing a message.
c. setting alerts.
d. setting security levels.
Answer:
a) An actor represents a user or another system interacting with the system being modeled.
c) An actor can initiate and participate in use cases.
Explanation:
- Statement A is true because an actor is an entity that performs a role in a particular system. This entity can be a human user, hardware, or another system.
- Statement B is false because an actor does not necessarily have to be a physical person. As mentioned above, it can be a system, a piece of hardware, or even another software system.
- Statement C is true because actors in a use case are the ones who initiate the use case and participate in it.
- Statement D is false because an actor can be part of multiple use cases. It's quite common in systems where a single actor (like a user or another system) interacts with multiple parts of the system.
Hope this helps! :)
CPUs are made mostly of crystalline silicon. First, though, that silicon must be purified. This is one of the most critical steps, because even a minute trace of impurities can cause chips to fail. Once in purified form, the silicon is formed into wafers, which are simply thin sheets crystalline material.
Then, the CPU maker etches lines onto the surface of the wafer. This process is followed by the actual placing of transistors and circuits.
Then the wafer is thoroughly cleaned with chemicals to ensure there are no contaminants. And finally, the wafer is precisely cut into the many individual chips, or CPUs, which will eventually provide the horsepower for your computer.
WWW/ World Wide Web.