Question

there is no such thing as a free lunch is a famous economic experession that means everything has a cost, In 1 or 2 sentences, describe how this expression relates to opportunity cost

Answer 1

If an opportunity arises, you need to put forth the effort to make it work. You cannot sit back and wait for something to fall into your lap, you have to seek opportunities because you have to work for what you want. Nothing comes for free.