An art gallery has eight new paintings, all the same size, but enough room on the wall for six of them. how many ways can the director arrange the eights paintings on the wall? 28 48 20,160 40,320

That would be 8P6  = 20160 answer

The order matters.

objects can be chosen out of objects, when the order matters, in ways.

So, the answer is ways.

go on the tube you might find some information there

this is answer of 144 cubic meters