Lambda pricing limited to account or organization?

I have an organization and with in that organization we have 3 accounts.

All 3 accounts have been created month back and the master account of the organization is more than a year old.

I have Lambda function in all 4 account(including the root account).

I know lambda offers 1M free requests per month and 400,000 GB-seconds of compute time per month.

My question here is:

1. Is 1million request per account? or spread through out my organization?
2. Is my organization (root account) still valid for 1M free request? If the request are with in 1million?