Find the Area of the Figure using addition or subtraction

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angles. measure need asap

He concluded that a heavier object dropped from the same height as a lighter object will land

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