You are right, even though Bitcoin is not stable, but Bitcoin has shown good progress, Bitcoin has slowly begun to rise, this is the beginning of the recovery of Bitcoin.

Bitcoin is a digital asset developed in 2009 by someone with a pseudonym Satoshi Nakamoto. This digital asset is like gold, but is only available in the digital world. The concept might sound like eGold, although it's actually a lot different.

There are 2 ways we can do to get bitcoin for free, namely:
Mining with a free Mining Cloud without a deposit
Faucet Collection.
The two methods above do require a relatively long time, because Satoshi (the smallest bit of bitcoin) that we get is very little, but it doesn't hurt if you want to try to collect it. and much more.

Almost everyone knows Ethereum is a good and potential coin, in my opinion this is not surprising, because Ethereum is a smart contract platform.

I don't think in that direction, in my opinion BCH cannot replace Bitcoin, because bitcoin is a coin that is very popular and has good potential.

Yes, even though Dash is down and unstable now, but I keep holding it until the price goes up again, I believe Dash is a good coin and has a good future.

Yes, Litecoin is indeed profitable, now prices are declining, this is the right time to buy it, and holding it back to the moon, I believe in the future Litecoin prices will go up and that is very profitable.

In 2018, the crypto market price is very weak and unstable, I believe the beginning of 2019 will definitely change, a good idea to invest we must choose coins that are good, potentially and have a bright future.