Thank you very much prof @sapwood.
I still have another post that has been graded but no upvote. It's 6 days old.

Here is the link.
https://steemit.com/hive-108451/@ederra/steemit-crypto-academy-season-4-beginners-course-task-5-bitcoin-cryptocurrencies-public-chains-home-work-task-for-stream4u

Thank you once again prof.