***** NOT A TEACHER *****
Hello, BigC:
You have received the answers from two teachers, and I definitely suggest that you follow their advice.
I feel, however, that you might be interested in the opinion of an old book written by a man who is still respected by many people.
His name was H.W. Fowler.
His book was published in 1926. It's entitled A DICTIONARY OF MODERN ENGLISH USAGE.
Accordng to Mr. Fowler, both sentences are grammatically correct:
Explain what are the duties.
Explain what the duties are.
According to Mr. Fowler, "it can hardly be said that one is more normal than the other."
According to Mr. Fowler, the first sentence would have this answer: These are the duties; the second sentence would have this answer: The duties are these.
*****
P.S. If you find his explanation difficult to understand, don't feel bad. Many people joke that a person deserves a medal if s/he tries to understand much of what Mr. Fowler wrote. I notice that the above explanation is missing from the 1996 edition. I found it in the 1965 edition`on page 279 ("indirect question").