Power Query

Question 1

Technical Date syntax

Answer 1

Year month day

Question 2

Technical date conversion (via formula)

Answer 2

use comma and the convert function

Question 3

Time - Duration

Answer 3

Select end of first and after start and then in add column use the Duration option

Question 4

Date and number from a file where used a different region setting: Answer two options

Answer 4

Option a: Use Locale in your Type Transformation

Option b: Use Query Option setting Current Workbook