Question 1070897
(i) The clock makes no difference.
You figure out how to choose the 6 books and line them up,
and then just make a space in the middle of the row of 6 books
to place the clock There are
{{{8*7*6*5*4*3=highlight(20160)}}} ways to do it,
permutations of 6 objects taken from a set of 8.
 
(ii) I interpret that question as meaning that
you cannot pout only 1 or 2 of the music books on the shelf.
It is either all or none of them,
and since excluding those 3 music books leaves us with only
{{{8-3=5}}} books, and we need 6,
the 3 music books go on the shelf in one of {{{red(2)}}} ways:
on the left of the clock, or on the right.
We still need to figure out in which order
(from left to right) we line them up.
That gives us {{{3*2=green(6)}}} options.
Then, there are the other 5 books
for you to decide what to do w it them.
You need to pick 3, and decide in what order to display them.
That gives you
{{{5*4*3=60}}} different options.
All in all there are
{{{red(2)*green(6)*60=highlight(720)}}}
ways to do it.