How base two and base sixteen are related?

Answer 1

the digits in base ten are: ones, tens, hundreds, thousands, etc.

in base two it's: ones, twos, fours, eights, sixteens, thirty-twos, sixty-fours, one twenty-eights, two fifty-sixes, etc.

in base sixteen, the digits are: ones, sixteens, two fifty-sixes, four thousand ninety-sixes, sixty-five thousand five hundred thirty-sixes, etc.

so every fourth place of base two is also a digit in base sixteen.