When it was his birthday, my uncle Isaac told me: ``$3$ years ago, my age was a square number. Next year it will be a prime number and in $12$ years\textquotesingle{} time, it will be a cube number." How old is lsaac?  Circle the correct age:  $28                39                52                  84$ 
Overseas Competition->Knowledge Point->Combinatorics->Logical Reasoning->Reasoning by Conditions->Complex Reasoning 