computer network is the answer
Answer:(1) To manage the computer's resources, which includes central processing unit, memory, disk drives, and printers, (2) To establish a user interface
(3)To execute and provide services for applications software.
The old mainframe computers have
(1) low memory sizes
(2) slower connectivity speed
(3) Larger sizer
(4) low sophistication.
Explanation: Operating system is a system software that manages the computer resources,helps to establish user interface and it helps to provide services for application softwares.
Operating system software includes WINDOWS X,WINDOWS 7,WINDOWS 8,LINUX,etc.
Mainframe computers are computers used by large multinational companies for processing bulk data. Old mainframe computers were produced by IBM(INTERNATIONAL BUSINESS MACHINE) in the year 1952 they are classed two scientific and commercial mainframe computers with different information although they had some incompatibilities. Old mainframe computers are large in size with low processing speed, sophistication and storage compared to present day system.
your account has enabled profile pictures for your users, you can manage all profile pictures for your account. Profile pictures are public and automatically approved when users upload an image in their settings. Using profile pictures can make it easier to see the users in your account and managing them gives you the ability to keep the pictures appropriate.
If Gravatars are enabled for an institution in account settings, and a user has a Gravatar but chooses not to upload a profile picture, the Gravatar will display for the user's profile picture.
If a student views another student's user details in a course and reports a profile picture as inappropriate, you can review those profile pictures and approve, lock, or delete the picture. In the courses, instructors can remove profile pictures completely from a user's details page.