Food chain that contains a producer, primary consumer, secondary consumer and tertiary consumer

What is an animal that lives by preying on other animals

Ageologist determines that a sample of a mineral cant be scratched by a steel nail but can be scratched by a masonry drill bit based on this information the sample mineral has to be softer than

Sediment layers stop lateral spreading when: they encounter a barrier they encounter an opposing current they run out of additional sedimentary material