Because i know i answered the questions, if you read the screenshots properly, you will get the points i made. The only thing here was i didnt use block one and block two to explain, rather i used block 2 and block 3.

This screenshot answers for "how the block hash works"

This screenshot answers "what if the middle of the block is changed."

So pls, if you read properly, you will get the clear explaination because the score you gave for this work is quite low. Thank you Prof. @stream4u as i await your reaponse.