1.Difference between MULTIPLEXER and ENCODER
2.What is DATA SELECTOR?(multiplexer)
3.Give advantages of mux,demux,encoder,decoder,magnitude comparator.
4.What are the minimization techniques available.
5.What is TTL and state its characteristics.
6.What are sequential circuits.Give example.
7.Difference between LATCH and FLIPFLOP.
8.What is a register.
I would prefer you do some research to see what you can find in google about these and if you still have questions ask them here.
Choosing the easy solution is not always the best way to learn.