Question

How would you calculate The number of seconds in a 40-hour work week

Answer 1

this is teaching you how to multiply by 1 (creatively) to change your units:
hr/workwk to seconds/workwk

we sart with:
40 hrs/workwk(60 min/1hr)(60 s/1 min) = canceling the units and multiplying = number sec/workwk