Answer:
C. 35
Step-by-step explanation:
First, let's put the first notebook.
1 2 3
1 2 4
1 2 5
1 2 6
1 2 7
We lose 1 step at each time.
1 3 2 is not ok because 1 2 3 is same as 1 3 2
5+4+3+2+1
Next, the other one.
4+3+2+1
3+2+1
2+1
1
5+4+3+2+1+4+3+2+1+3+2+1+2+1+1=35
35 different ways
