20 Compute Units.
Reference: Here
Parameters
None
Returns
ledger_hash(string) The unique hash of this ledger version, in hexadecimal.ledger_index(unsigned integer) The ledger index of this ledger version.
{"id":1,"command":"ledger_closed"} to wss://mainnet.xrpl.validationcloud.io/v1/<YOUR_API_KEY_HERE>.