Danny is picking out a new skateboard. The board can be grey or black, and the wheels can be pink or yellow. The decal on the skateboard can be a star, a wolf, an eagle, or a tiger. How many different combinations does Danny have to choose from?

Which of the following statements is true? a. the irrational number system is not closed under multiplication, because the product of two irrational numbers is always a rational number. b. the irrational number system is not closed under multiplication, because the product of two irrational numbers is not always an irrational number. c. the irrational number system is closed under multiplication, because the product of two irrational numbers is always an irrational number. d. the irrational number system is closed under multiplication, because the product of two irrational numbers is always a rational numbers. reset submit