3. How many words being exposed for electrum and nano ledger s would you consider your seed a bit compromised? Obviously if you give 1-2 words out for electrum or nano ledger s... that is still very safe right? But obviously electrum is not as safe because less words. If someone has your first 6 words of electrum or the last 6 words... how long would it take to brute force that? What about ledger with 12 words... say someone found one half of your 24 word seed?
12-words is indeed less secure than 24 but that doesn't make it unsecure.
If the attacker if bruteforcing the words than the "
entropy", then just base it from the number of possible permutations;
like for example, 6 out of 12 words was compromised:
2048^6 = 73,786,976,294,838,206,464 which still a lot for a regular computer but you can consider it compromised.
For leaked 1 or 2 words, I can tell that it's not enough to be compromised.
keep in mind that while this is theoretically correct, realistically the situation can be very different. if a portion of your seed phrase is leaked it is reasonable to assume the entirety of it could also leak because there is something seriously wrong with your security! so in a situation where you know some number of words of your seed phrase is leaked you must create a new wallet and transfer all your funds to that one.