Step-by-step explanation:
Using Pythagorus theorem:

Therefore,

I don’t think this will help exactly but I hope it does x
Answer:
D, 20:30
Step-by-step explanation:
At first glance, this does not seem like the correct ratio. But I'll spare you a long intro and get into it:
20:30: Divide both of them by 10
=2:3
2 x 12:3 x 12
24:36
Hope this helps!
1, 3, 5, 7, 8, 11, 13, 15 is the answer.