I'll do the first one:
Both novels.
Student 1 picks a novel. There are 3 novels out of 6 books total.
Now there are 5 books left.
Student 2 picks a novel. There are 2 novels out of 5 books since the other student took a novel.
To find the probability you would multiply the probability student 1 gets a novel and the probability student 2 gets a novel.

So the probability is 1/5. Or 20%