Order the Books:

Book: $18.99
Shipping (Media Mail within the USA): $3.45
Maryland 6% State Tax: $1.14
Total: $23.58

Book: $15.00
Shipping (Media Mail within the USA): $2.89
Maryland 6% State Tax: ¢90
Total: $18.79

Book: $9.99
Shipping (Media Mail within the USA): $2.89
Maryland 6% State Tax: ¢60
Total: $13.48