This topic is about Oracle Certified Professional Java SE 11 Programmer 1 Study Guide (ISBN: 978-1-119-58470-4), by Jeanne Boyarksy and Scott Selikoff.
I found possible errata in the answers of the review question of chapter 2 or chapter 2 itself. On page 53 table 2.3 states that the default initialization value of a long is 0. However, the answer of a review question about this topic (question 8) on page 495 states that the default initialization value is 0L. Should it be 0 or 0L?