Operating System (OS) is the answer.
An application runs in/on an OS. It is not the OS itself. Like Word or Chrome are applications.
Systems is too generic and not specific enough to mean anything in this context. Throw away answer.
Network Operating System does not 'usually' run on a hard drive but on memory chips in things like routers, wireless access points and switches that move network traffic.
Answer:
A: used by ISP's to filter out email SPAM
C: a way to help an individual focus on best choices when deciding what to watch or buy.
Explanation:
Collaborative filtering uses a community-based approach to filter spam. It works by collecting numerous email users from around the world. By doing this, it becomes possible for users to flag emails that are spam and those that are legitimate.
Also Collaborative Filtering is one of the most efficient techniques for building a system that can help a user when it comes to recommending best choices based on information from a large number of users.
Answer
The answer and procedures of the exercise are attached in the following archives.
Step-by-step explanation:
You will find the procedures, formulas or necessary explanations in the archive attached below. If you have any question ask and I will aclare your doubts kindly.
