What term is used to describe genetically identical twins?

Although the United States was founded on the principle that "All men are created equal," the U.S. Constitution allowed for slavery. This contradiction was called the __________ by Gunnar Myrdal

Fill in the blank(s) with correct word

Rebecca tells Tom that he is singing "off pitch.". Rebecca is referring to which physical property of sound?

a. Amplitude b. Frequency c. Loudness d. Speed e. Decibel