Answer
See explanation
Work Step by Step
a. The role of user interface or UI in operating system is to allow a user to enter or recive information. There are mostly two types of UI of operating system we can see in most of the pc's, they are text based UI and graphical user interface (GUI). A text-based user interface displays text, and its commands are usually typed on a command line using a keyboard. While GUI uses icons, menus and other functions to manage interaction with system.
b. The kernal is main central part of the operating system. It is the core that provides basic services for all other part of the OS. It is the main layer between the OS and hardware, and it helps with process and memory management, file systems, device control and networking.
