Welcome to your interview.
The question is on your right: Weighing Puzzle Minimum Steps. Take a moment with it first.
Talk your thinking through with me if you like - when you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes). Discussion and graded submissions share your five interviewer interactions, so spend them well.
There are 8 identical-looking balls, but one is slightly heavier than the rest. Using a balance scale, what is the minimum number of weighings required to find the heavier ball?