Answer:
Adrian requires a high speed internet connection and a codec player to download and run movie on his system.
Explanation:
There are some basic requirements of the computers that, can be used to watch the movie on the computer.
1. RAM
2. Storage space to store the movie
3. High Speed Internet: As the movie is on the internet, to download it from internet, bandwidth and speed of internet is required.
4. Video Codec Player is required to play a digital movie on laptop or system.
Answer:

Explanation:
A computer network is a network of computers that can share data among the computers.
Answer:
i not know mainframe computer there is many use of computer
Answer:
A primary key is a special relational database table column (or combination of columns) designated to uniquely identify each table record. A primary key is used as a unique identifier to quickly parse data within the table. A table cannot have more than one primary key.
Primary Key.
Candidate Key.
Alternate Key.
Super Key.
Composite Key.
Foreign Key.
Unique Key.
In the relational model of databases, a primary key is a specific choice of a minimal set of attributes that uniquely specify a tuple in a relation. Informally, a primary key is "which attributes identify a record," and in simple cases constitute a single attribute: a unique ID.
Explanation: