We can expect market will be bullish within that time. So it sounds possible to have 4x return from your 40k$. Bitcoin and ether are always safe for investment. Recent merge of ether may decreased its price but not that much. So its an opportunity to have btc and ether. Solana has many problems that are still unsolved. But you may consider solana by investing little amount like 3/4k$. Cause 2years is long time and we may see significant change on solana blockchain. metaverse token Sandbox is also can be consider
If we want a safe investment for the long term, we definitely have to invest in Bitcoin and Ethereum. In addition to always dominating
the market, both Bitcoin and Ethereum also have a good track record. So it is quite reasonable if we end up expecting a profit of up to 4x
from the long-term investment that we make. Regarding investment in Solana, we really have to be more careful, because as you said Solana
there are still some unresolved problems. But because Solana is a potential coin, I still recommend Solana as an investment option that
we can take. But of course we can't allocate too much money to invest in Solana and we still have to focus on investing in Bitcoin and Ethereum.
Because investment diversification is a very good thing to do, it never hurts to try investing in other altcoins that we consider potential.
But make sure to do research and analysis first to make sure we are not wrong in choosing projects for investment.