How to express concrete method in abstract class on UML2 Class Diagram?

Problem mentioned in the underlined sentence in this image:

I have been asked to add concrete public method in a abstract class in UML2. I am struggling to find the solution as I didn't find any material related this. I know that abstract class can be defined by italic font. But how concrete public method in abstract class?

Please, if you have the solution, leave an answer.

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