Answer the following questions.

$1.$How to input a numeric string $($such as $001$ in "serial number"$)?$

$2.$ Please list two methods for entering multiple lines of text in a single cell.

How to set the format for displaying dates?

What is the function of the filling handle? How to make data automatically fill in$?$

How to set the validity or validity range of data? How to set an error warning when invalid data is input?

How to add "annotations" to cells?

How many worksheets does a workbook contain by default? How to create, copy, clip, delete, and rename worksheets?