This is a system of organisms or things ranked one above another

Match each description of an object’s motion with the position-time graph that represents it. not moving moving with constant speed speeding up slowing down

Which statements explains what the fossil records indicates? check all that apply. a) earth is 4.5 billion years old b) many organisms have become extinct c) mammals have always existed on earth d) mass extinctions have occurred several times on earth e) the amount of water on earth has decreased over time?

Why is planting a wide variety of plant species better than planting only one type? a) diversity is best for the environment. b) a wide variety would mean less wear and tear on the soil. c) it would lead to desertification prevention. d) combining biological and chemical controls are the conditions of a healthy farm.