I.
After every 16 clock pulse counter reach to initial state.
After 32 clock pulses counter will be at 0110
after 33 clock pulse, 0101
After 34 clock pulse, 0100
After 35 clock pulse, 0011
After 36 clock pulse, 0010
After 37 clock pulse, 0001.
II
After Every 16 clock pulses counter will be at initial state, 0110
37 mod 16 = 5.
As it is a down counter, it will be 5 states down from 0110 = 0110 - 0101= 0001.