Book and card

[TT]

   Dear Mr/Ms

       My name is Thi Tran. I bought your product. Now I need some information.

       I have a book, I have a card, but my classcourse doesn't use this card. I have a book question as picture.  I don't have any course class. I want to check the expalnation example in the book. How can I do?

    Would you like to instruct me how to check solution for my problem? I appreciate your response.

I am looking forward to hearing from you.