Permutation problem involving item order

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A professor writes 35 true/false discrete mathematics questions. The answer to 14 of these are true. How many different answer keys are possible

  • a) if the questions can be in any order?
  • b) if every true statement is immediately followed by a false statement?

For the part a), I know it is simply ${35 \choose 14}$. I am having trouble with part b), where if every true statement is followed by false.

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Pair every true with its following false and make a list of the $7$ false answers and the $14$ true/false answers