Answer:
The simple subject is "hours".
Explanation:
The simple subject is "hours" because The simple subject is one that has a single nucleus. The subject's core is a noun or pronoun. In this case: hours. The simple subject is distinguished from the compound subject, which is one that has two or more nuclei.
A subject can be simple even if its nucleus is plural. For example: Children play in the garden. ("Children" is a plural noun, but it is still the only core of the subject, so it is a simple subject).
