Random question?

Which of the following materials would best slow the transfer of heat?

Random question?

The fur color of a bear varies with its environment. Polar bears found in the Arctic have white fur, while black bears found in Pennsylvania have dark fur. Which best describes the variation of fur color amongst the bear species?

Random question?

Index fossils help scientists estimate the age of a rock because index fossil species only existed for a relatively short time. What happened to the species that are now used as index fossils?

Random question?
Over geologic time, global mean sea level has varied significantly. Which change is most likely responsible for an increase in global mean sea level?