There are some books on the desk Is this sentence right

There are some books on the desk Is this sentence right

yes

What___ on the desk?There___ A dictionary, three books and a pencil box on it

Both are
Because the person who asked didn't know what was on the table in advance, he was the first to use is
Because the singular and plural of be in there be are determined according to the nearest noun after it, the second is

What's that on the sofa and what's on the sofa are it's... And there's, respectively
The former answers with a pronoun because it has that, and the latter answers with there be because it has place?

What is that? Answer with personal pronoun it
What is there on the sofa