Would the sentence below be:

SIMPLE, COMPLEX,
COMPOUND, or COMPOUND COMPLEX?

The students prepared for the exam,
and the instructors administered it
on Thursday.

Would it be a compound sentence?

You are right. These are two independent clauses, since each would stand as a separate sentence. Thus it is a compound sentence.

I hope this helps. Thanks for asking.

I washed and vacuumed the car

I washed and vacuumed the car

Yes, you are correct. The sentence "The students prepared for the exam, and the instructors administered it on Thursday" is a compound sentence. It consists of two independent clauses joined by the coordinating conjunction "and." Each clause can stand alone as a separate sentence.

To determine if the sentence is simple, complex, compound, or compound-complex, you need to analyze the structure of the sentence.

A simple sentence consists of one independent clause, which is a complete thought.
A complex sentence consists of one independent clause and one or more dependent clauses.
A compound sentence consists of two or more independent clauses linked by coordinating conjunctions like "and," "but," or "or."
A compound-complex sentence consists of two or more independent clauses and one or more dependent clauses.

In the given sentence, "The students prepared for the exam" is an independent clause, and "the instructors administered it on Thursday" is also an independent clause. They are connected by the coordinating conjunction "and." Therefore, the sentence is a compound sentence.

In summary, the sentence is classified as compound because it consists of two independent clauses linked by the coordinating conjunction "and."