Invest your 20k in gold because its too much to invest in bitcoin. If bitcoin fails then you lose your 20k and thats not what you want to happen. Gold will keep value so your money will be kept safe probably even more safe than a regular bank.
20k usd is not a big amount of money to invest in the bitcoin. The gold price will rise slower than the bitcoin.
True gold might rise on future too but still it's slower compared to Bitcoin but in gold you could assure making profits on Long term but if you like to see profits on short time or on couple of years then it's fine to invest in Bitcoin but remember the risk involved on it.