Answer:
The translation for this is: All the cabins in the ship have a bed.
But the reason "Todas" instead of todos is because cabins in spanish is a word finishing in "A" vowel letter.
Explanation:
All right, objects that can be used as subjects have a certain characteristic in Spanish. If they end in a vowel letter they are assigned a female gender. Therefore they need to be accompanied by direct objects like "la" or "las" depending on their number. This is the direct object used for the female gender. Now, the termination a or s depends on the number of objects. In our case are several so it's plural.
