PCA (Prometheus Certified Associate) sample exam question with answer 378

Question:
Which of the following time durations is NOT valid for use in a range selector?

1. 1y
2. 100ms
3. 1m30s
4. 1mo

Answer:
D - is the correct answer. Months are not allowed for use in range selectors as they vary in the number of days they contain. More at time-durations
A, B, C - this time duration is valid for use in a range selector