You earn 3/4 of your sales. what dollar amount of sales do you need this week to earn 600

What is the value of the digit 1 in the number 13?

Any is very appreciated! (picture is provided below)not sure how to do this at all won't lie

Which shows the correct lengths of side c in both scales? scale 1: 45 m; scale 2: 60 m scale 1: 60 m; scale 2: 45 m scale 1: 36 m; scale 2: 27 m scale 1: 27 m; scale 2: 36 m mark this and return save and exit