Mining is complex business.
There's electricity and heat costs, and even though you say you're not running it for a profit these costs can lead to a substantial loss(depending on where said person lives) which doesn't make it worthwhile.

Also having just one miner won't give you any substantial hashrate so I fail to see the point of buying one in the first place.
If the total hashrate of the network was low enough that having just one miner would give you a decent shot at finding a block then it would be a good idea, otherwise it's pointless, really.
Running a bunch of low hashrate miners doesn't give you a shot at finding a block so it doesn't make mining "more decentralised"

Ditto with forming or joining a pool, if the pool gets big enough it leads to the same problems you're trying to solve.

Increasing hashrate does nothing to unconfirmed transactions.
Unconfirmed transactions are as a result of the bitcoin block size (now block weight)
There will always be an average of 1 block every 10 minutes no matter the hashrate -- even if we could harness the full energy of the sun.

If you want lower fees then use segwit and tell others to use it also.

There is no global mempool.
Each node has its own mempool, so even if a transaction is present in one node's mempool but not others, it could be marked as spent by your wallet .
Also, of its removed from one node's mempool, it could be present on the mempool of other nodes.

By "ethereum" I assume you mean Electrum.

Blockchain.info wallet transactions are not flagged as RBF, so you'll be unable to RBF them later.

If you're in possession of the private key of the receiving wallet, you can  do CPFP.
You can't CPFP from the sending address because there's no change (child) output.

If you're the RECEPIENT and have the private key/seed of that address then import it into Mycelium wallet for Android and make a CPFP transaction from there.
On the transaction tab, highlight the transaction, press the menu button and select "bump fee/ CPFP"
This will create a CPFP transaction and make both the parent and child transaction confirm.


If you're not in possession of the receiving address private key then you simply have to wait for up to 2 months or more for all nodes to drop the transaction from their mempool.

bitcoinfees.21.co gives you an estimate fee in satoshis per byte.
To know the  exact fee you'd need to know the size of your transaction, then multiply it with the fee in Satoshi per byte.

Right now the recommended fee for quick confirmation is 490 Satoshi's per byte. the most common transaction type of one input and 2 outputs is 226 bytes.
Multiplying both of them gives you 106,220 Satoshi's, which is ~ 0.0010622BTC

The total fee will differ depending on the size of your transaction.

This is a script that does it for bitcoin. https://github.com/dan-da/hd-wallet-addrs
BCash is similar to bitcoin so you just have to change the API to query BCash block explorers instead

Native segwit is Bech32 (starts with bc1), and it's better because a standard transaction of 1 input and 2 outputs is 141vbytes, which is 38% less than "legacy" P2PKH transaction, so you save 38% on fees.
Unfortunately it's not common YET, so not many wallets can send funds to it.

I can think of a few ways...
You can use Ian Coleman's BIP39 tool(remember to download the Website and access it from an airgapped  PC) if you have the seed phrase (BTC and BCash have the same address derivation scheme)
It will create the list of bitcoin addresses from the seed (same thing the xpub does)

If you don't have the seed then
You can use something like this: https://github.com/dan-da/hd-wallet-addrs
But edit it to query BCash block explorer APIs instead of bitcoin's so you can get the balance of the addresses.

There might be easier ways but I'm sleepy and can't think of anything better now

If you make another transaction (spending the unconfirmed outputs) it won't get confirmed until either the first transaction is confirmed.

An exception is a Child-pays-for-parent transaction which spends the unconfirmed outputs from the pending transaction but with a high-enough fee that past for both transactions so they both get confirmed together.

I'm not familiar with Multibit so I can't tell you how to make a CPFP transaction with it.

The Samourai Sentinel app has that ability.
You can check their source code for what you need:
https://github.com/Samourai-Wallet/sentinel-android?files=1

Or you can check Electrum: https://github.com/spesmilo/electrum/blob/0a648e2b1cdb7852d80c0626c62984ef01c1c7e9/lib/bitcoin.py#L50

Everything works fine here...
https://blockchain.info/unspent?active=13STWgarJY21fZAHhNMsA3bia5L52zx5qv&format=html

Blockchain.info Is a BITCOIN block explorer.
It won't work for an altcoin like BCash.

This is a BCash block explorer: https://blockdozer.com/insight/

Unfortunately, no BCash block explorer can search for xpub.

If you want to, you can do it manually by deriving the addresses from the xpub and checking them on a block explorer.

I don't know about Exodus -- don't use it because it's not secure (forces address reuse, closed source, allows insecure passwords, etc)
You can import your private key/seed phrase into Mycelium wallet on mobile to make a CPFP transaction.

When you import your private key, go to the transaction tab, highlight the unconfirmed transaction, press the menu button and select "bump fee/CPFP"

This will create a new transaction spending the unconfirmed outputs with a higher fee for both transactions, so your new transaction and pending transaction from the bitcoin ATM will be confirmed at the same time.

The operator can't do anything. (Technically they could do a RBF, but that's not gonna happen)
It's up to miners to confirm the transaction or not.

If you want your transaction to confirm quickly and you don't mind paying extra FROM your received bitcoin then you could do a CPFP transaction spending the unconfirmed outputs from that transaction with a high-enough fee that pays for both transactions.


Or you could check the Service section to see if you can get a miner to confirm the transaction.

The "Mercatox Tx" is an internal tx hash for the Mercatox exchange, not the bitcoin blockchain.
You can see that the field for network hash is empty.
If they pay out the transaction you'd see a valid bitcoin transaction ID there.
Exchanges usually don't send out bitcoin withdrawals immediately but batch them to save fees.
Your transaction hasn't been sent yet.
The receiving bitcoin address 19Boxxxxx hasn't received any 0.036 BtC

You're not supposed to store seeds online.
Also, you're needlessly complicating issues.
You can write everything down on a paper and store it in an offline location like a safety deposit box.


If you want to split your seed, then you wouldn't store it in plaintext, but instead using something like Shamir's Secret Sharing.
The website below gives a demo
http://point-at-infinity.org/ssss/demo.html

You can give a BIP 38 encrypted private key, and with the way it works, the password acts as part of the seed phrase so the person can't access the bitcoin without it.
BIP 38 encrypted private keys usually start with 6P...

This is of course assuming that you chose a very strong password with a long length. You can throw in a few UTF-8 characters to guarantee that it won't be broken.

Yes. That is correct.

That is possible also, but the probability of you winning a block is very low.
Unless you have a large hashrate.
You can fill only your transaction in the block, you can choose not to include any transaction except the Coinbase transaction if you wish (like Antpool does)

If, by a stroke of luck, you actually solve the block with your transaction included the transaction will have 1 confirmation (yours).
Any other block any miner mines will build ON TOP of YOUR confirmed block and the number of confirmations will increase with every valid block mined on top of it.

Yawn.
Every time an idiot wants attention hs/he writes something about bitcoin.

The mathematical techniques used to secure bitcoin did not fall from the sky, neither are they being used in isolation in only bitcoin.
It's also used to secure a whole lot of things other than bitcoin so even if ECDSA is broken, bitcoin wouldn't be the first target.
Also, bitcoin could always be forked to a quantum resistant algorithm.

Usually this is solved by making another tiny deposit to the same address.
That should push the previous transaction to be acknowledged by the system.

Apart from a support ticket you can try this also.

The answer of the puzzle IS the private key.
So if you have indeed solved the puzzle, you'd have the private key.
You can use Electrum for desktop or Mycelium for mobile to import/sweep private keys.

What that means is that you can't do a Replace-by-fee transaction because your total amount won't be able to increase the fee sent.
If you did a RBF your just be able to increase your fee paid from 227sats per byte to 233 sats per byte, whereas the current recommended fee according to bitcoinfees.21.co is ~490sats/byte for quick confirmation.

If you're the owner of 13EiZrXRgBCZRYixm4EhJnTELnyveZaFC6 (i.e the receiver of the payment) then you can attempt a Child-pays-for-parent transaction by spending the unconfirmed outputs from your transaction but paying enough fees to cover both transactions.
This could be expensive, but if you want the transaction to be confirmed quickly then it's recommended.

Another (free) option would be to forward your transaction ID to mining pools like ViaBTC or Antpool.
You can also contact Quickseller (runs f2pool) to add your transaction to the next block they mine.