Design a counter to count even numbers between 0 and 15. Therefore states will be 0 -> 2 -> 4 -> 6 -> 8 -> 10 -> 12 -> 14 -> 0. If any unused state is encountered bewteen 0 and 7, then the counter should go back to initial state 0. If any unused state is encountered between 8 and 15 then the counter should go back to initial state of 15. Use T-flip flops in your counter design.

a. Draw state diagram and state table

b. Draw k-maps and show logic equations

c. Draw hardware logic diagram using AND-OR logic and T-flip flops

d. Draw hardware logic diagram using decoder and T-flip flops

e. Draw hardware logic diagram using multiplexer and T-flip flops