The quotient of three less than twice a number and the number squared

Ammonia molecules have three hydrogen atoms and one nitrogen atom.how many of each atom arein five molecules of ammonia

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

A+b= 17, ab=70, find the value of |a-b|