For the state diagram shown here how many D$-$Flip$-$Flops will this machine take if the states are encoded in binary?

For the state diagram above, how many D$-$Flip$-$Flops will this machine take if the states are encoded in gray code?

For the state diagram above, how many D$-$Flip$-$Flops will this machine take if the states are encoded in one$-$hot?

For the state diagram above, is this a