Answer:
I can be found in seconds, minutes and centuries, but not in days, years or decades.
How many months of the year have 28 days?
They keep secrets locked away. And you pass through them each day. For each one there is a key, They respond to sesame.
What can be measured but has no length, width or height?
Can be achieved in a car or as a position during conflict
What is always coming but never arrives?