Answer:
What is easy to spot but hard to find?
I am commonly abbreviated to H
I can be repeated but rarely in the same way. I can't be changed but can be rewritten. I can be passed down but should not be forgotten.
I shrink smaller every time I take a bath. What am I?
Which vehicle is spelled the same forwards and backwards?
No matter how little or how much you use me, you change me every month.