Q: What is the substance called whenatoms of different elements join together? Choices: - crusts - crystals - plants - compounds A:
compounds

Q: Aging is associated with the death of what? Choices: - proteins - genes - muscles - cells A:
cells

Q: Which theory explains how populations of organisms can change over time? Choices: - free by natural selection - changes by natural selection - intelligent selection - evolution by natural selection A:
evolution by natural selection

Q: Glaciers modify the landscape by what? Choices: - silt - sediment - truncation - erosion A:
erosion