Make sure that you understand what mutability means relative to the concrete code. Explain it to your fellow programmers!
More specific, can you argue for or against the claim that a Die instance/value should be mutable?
And similarly, can you argue for or against the claim that a Card instance/value should be mutable?
Why is it natural to use structs for immutable objects and classes for mutable objects? Please compare your findings with the remarks in 'the solution' when it is released.