How to check if button is clicked in angular.

Nathan wants to create multiple worksheet containing common formatting styles for his team members. which file extension him to save these worksheets? nathan to create multiple worksheets with common styles. he needs to save them with the extension.

Im doing this last minute and literally none of my neighbors or people that my dad works with use excel so if anyone could me make up an example

Which network media uses different regions of the electromagnetic spectrum to transmit signals through air? uses different regions of the electromagnetic spectrum to transmit signals through air.