Final answer:
Zack can answer 6 questions in 6 minutes, as he answers at a rate of one question per minute. Therefore, the answer is 6 questions.
Step-by-step explanation:
The question asks us to calculate how many questions Zack can answer if he answers at a rate of one question per minute for 6 minutes. To find the number of questions Zack can answer, we simply multiply the rate (1 question per minute) by the time (6 minutes).
So, the calculation is: 1 question/minute x 6 minutes = 6 questions.
Therefore, the correct answer to how many questions Zack can answer in 6 minutes is 6 questions, making option C the correct choice.