Answer:
Makel Green has been working hard all day; his friend, meanwhile, took a long nap on the couch
Explanation:
A conjunctive adverb, or otherwise known as adverbial conjunction is simply an adverb that joins two clauses in a sentence by modifying the verb it introduces with an adverbial modifier.
From the given sentence, "Makel Green has been working hard all day; his friend, meanwhile, took a long nap on the couch", the conjunctive adverb is meanwhile.
