A. $4.99
B. Books (B) < $5 OR Books (B) ≤ $4.99
C. The number line would begin at 5 on the number line with an open circle. The arrow and line point to the left.
Reasoning for each answer:
A. The cost of the books all cost LESS than $5. This means no book can be $5 or greater. With this in mind, $4.99 is the largest possible value of a book.
B. < means less than, and ≤ means less than or equal to. For this reason you could either write B < $5 (meaning that a book can cost LESS than $5) OR you could write B ≤ $4.99 (meaning that a book can cost LESS than or EQUAL to $4.99)
C. An open circle means that the number is not included we are trying to show that the value of the books are LESS than $5. Meaning, an open dot above 5 pointing to the left shows that a book can’t cost $5, but CAN cost anything LESS than $5.
I hope this helps! Good luck!