Q: Q: What is another name for mother of pearl? Choices: - pigment - enamel - calcium - nacre A:
A: nacre

Q: Q: Mixtures of materials called alloys contain at least one of what type of material? Choices: - coal - liquid - steel - metal A:
A: metal

Q: Q: Where does most of the sound we hear travel through? Choices: - water - light - the ground - air A:
A: air

Q: Q: How many mass distinctions have radically altered the history of life? Choices: - six - one - four - five A:
A: five