Final answer:
The probability that the second flip is heads when flipping a fair coin is 0.5. This is because each flip is independent and the probability of heads on any single flip of a fair coin is always 0.5.
Step-by-step explanation:
The question asks us to determine the probability that the second flip is heads when flipping a fair coin four times. Since each flip of a fair coin is independent, the outcome of the second flip is not affected by the first, third, or fourth flips. The probability of getting heads on any single flip of a fair coin is 0.5. Therefore, the probability that the second flip is heads is 0.5, regardless of the other flips' outcomes.