How trigger will fire on multiple rows insert in single transaction

I created a FOR INSERT trigger that will fire after inserting. Below are the different scenarios for which I would like to know how trigger will fire.

The trigger is on an employee table. I begin one transaction where I insert 4 rows. My doubt is how trigger will fire.

1. Will it fire immediately after inserting each row?
2. Will it fire after completion of all the rows in that transaction

We are able to access the inserted & deleted special tables from the trigger.

1. How many rows will be present in those tables each time? Only one record? Or multiple records?

Thank you in advance.