A. Once a transaction is made, it is made. There are no returns once it is confirmed. It is physically impossible to reverse a transaction on the blockchain due to the mining and proof of work.
A. All transactions are verified by math and final. There is no way to dispute, cancel, or duplicate any transaction made.
> 1. What do we mean when we say that blockchain has transaction finality/immutability?
Immutability meaning that it cannot be recreated nor replicated
And finality meaning that it cannot be undone.
Meaning any transactions done on the blockchain to make purchases with crypto, once the transaction has be approved, it cannot be undone.
2. How does this lead to the trustless environment that blockchain creates?
It creates trustlessness because you do not need peer-to-peer trust, but rather trust the network transaction.
The math and physics behind the blockchain secures the transactions rather than trusting the company or individual.
That it cant be changed or removed
Confidence in the veracity and Transparency
What do we mean when we say that blockchain has transaction finality/immutability?
we mean that once the transaction is processed , all of its data become part of a past data that cannot be changed unless a huge change is made and everyone in the process change the data as well so there has to be an agreement that willl change the trustworthiness of the data, so probably no one will agree.
How does this lead to the trustless environment that blockchain creates?
The current state that blockchain shows is final, no need to verify it, and if you verify it there is the highest probability that it is right.
Transaction finality/immutability means that data that is entered into the blockchain can not be changed. Whatās there is there. It has finality.
Finality leads to a trustless environment because it allows people to trust the protocol and not need to trust other people.
1 - once a transaction is added to the ledger, there is no way to remove it
2 - you dont need to trust other entities/people/companiesā¦ you can trust the blockchain network itself (and its undelying math & protocols)
1 - Any transaction cannot be reversed, it is final, trustless. If you send it, it will happen 
2 - Its immutable, it cannot be tampered with, you have 100% certainty that whatever transaction you make, it will happen. Its impossible to defraud the blockchain.
It means that once a consensus has been met on the network regarding a transaction, that transaction cannot be reversed, changed or deleted and is now the truth.
One example of trustlessness is when doing online business with a stranger. The buyer can send money, for a service or good, and know every step of the way where that transaction is on the blockchain, and therefore can know exactly when the merchant has received payment. On the flip-side, a merchant can have absolute confidence when receiving a payment because once they have, it cannot be reversed. This creates technical trustlessness.
What do we mean when we say that blockchain has transaction finality/immutability?
-> once a transaction is confirmed, there is no way of reversing it or editing it
How does this lead to the trustless environment that blockchain creates?
-> it means that people cannot scam the system in saying that they paid for something when they had not done so, as all transactions are recorded in a way that cannot be reversed
No take backs!! When a transaction is verified within the blockchain, there is no way to reverse it.
All transactions are verified by the network and miners
Once a transaction is verified and added to the chain would be impossible to remove it.
The trust in the trading party is replaced with trust in the chain. Once the chain is proven reliable, the entity can interact with any third party without worry about them.
What do we mean when we say that blockchain has transaction finality/immutability? It means that once a transaction is posted, there is no way of reversing or changing it. It is permanently recorded on the blockchain.
How does this lead to the trustless environment that blockchain creates? This removes a third party facilitating transactions between two parties and instead occurs directly between two entities. They both know that once they post a transaction on the blockchain, the value is immediately transferred from one party to the other, and there is no way of reversing it.
It means that transactions occur in the blockchain are irreversible,
once it is already on the blockchain it is already final, there is no more turning back, you cannot change it anymore. When you made any wrong decision in doing transaction in the blockchain, donāt regret it but rather you should learn from it, and move on because whatever happen in this world, life still goes on. When it happens it happens, its final and immutable.
This leads to an honest environment, because of blockchain being trustless this means the ones who will be using it can take advantage to use blockchain to transact to anyone(strangers) and to anywhere in the world since you donāt need to trust the people you are trying to transact, so this will give you more convenience and no worries because trust is already built in the blockchain. This trustless system can make the world a better place, because trust is one of the rarest thing in the world to find right now, specially to people.
What do we mean when we say that blockchain has transaction finality/immutability?
Once a transaction has occurred there is no way to reverse it. It is on the blockchain forever and impossible to change.
How does this lead to the trust-less environment that blockchain creates?
With transactions being irreversible and immutable a lot of trust is removed. Thereās no need to trust a 3rd party or central authority to facilitate the transaction. No chance of the transaction being reversed once product/service has been received. This allows strangers to business with each other.