Select all sets in which the number - 15 is an element. A. natural numbers
B. real numbers
C. irrational numbers
D. rational numbers
E. whole numbers
F. integers

Pls! does anybody know a shortcut for answering these types of questions in the future?

Terri makes a quilt using three sizes of fabric squares the side lenght of each fabric square is the square root of the area

The total cost of anja’s trip to the dentist was $628.35. she paid a flat fee of $89.95 which included the checkup and cleaning and then had 4 cavities filled, each of which cost the same amount. which shows the correct equation and value of x, the cost of each cavity filling?