How to lock your computer file?

Ans:- rt click on file-> properties-security-administrator-edit-administrator-check full control-ok-ok.

How to write paragraph in ms word

=rand(1,2,3,4)>press inter.

How to open Task Manager ,SignOut etc?    =ctrl+Alt+Delete. 

How to use a keyboard mouse? =Ans:- Left alt+shift+num lock.

*windows display zoom in and zoom out = windows + (+)