Question

will mark BRAINLIEST if you give a correct answer. Please don't forget about the proportion. Thank you!

Answer 1

The second proportion is correct and it will be 6 hours.

Answer 2

The Second One Is The One To Use 
The Answer Is 6hours
15h=90
Divde 
h=6 

~Hope This Helps :)
Need More Help With Question Just Inbox Me 
Also Rate, Give Thanks, And Mark As Brainiliest. 
Thank You ;)