VECELO Ergonomic Design, Adjustable Seat Height, Durable Attached Armrest, for Task, Home Office Work, Black, Mesh Chair

Are the arms detachable - in other words, can the chiar be used without the arms being attached. Our desk is too low for the arms height listed?

I've read several reviews commenting on the seat cushion being uncomfortable. Has anyone used a cushion successfully it mitigate the hard seat?

Can you lock the back of the chair at any angle? Or it is just "rocking "?

Do the wheels roll easily on carpet?