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https://www.coinbase.com/join/5953f37d9ac69f0648246642

Use this link to create a coinbase account and deposit $100 into any of the four choices and we both get $10 free bitcoin.

I would recommend putting money into ethereum and not bitcoin. I outline why here. Right now all cryptos have taken a major hit and history has shown that they tend to bounce back. Because of that, many enthusiasts would tell you to buy, but history is not truly an indicator of future price since people's valuations are subjective and cryptos in particular have no value aside from the technology that is behind them. I would recommend putting $100 in ether (ethereum) using the link I gave you (to get $10 free) and then use it to learn about smart contracts and the blockchain. Getting skin in the game and learning about is well worth the investment.

However, no one knows better than yourself when/what is the best choice to invest in. Do research, look for what is logical, and trust your gut over anyone else's.