The fossil record shows that the types of living things on Earth changed over time. Which fossil would most likely be found in the oldest rock layer?

After reading the paragraph below, answer the questions that follow. researchers have created a robot that has a very thin leg that is moved by cardiac (heart) cells contracting in unison. the robot, made of a polymer similar to that used in making contact lenses, is bathed in heart cells with supporting cells, which then attach to the robot and provide movement as they contract. all of the cardiac cells working together can cause the robot leg to move in a way that individual cells could not. this is an example of a. emergent properties of cells. b. energy flow through an ecosystem. c. adaptation. d. internal environment regulation.

When analyzing tree rings, what do scientists assume a thin ring indicates?

Acceleration is a direct result of a.) balanced forces b.) unbalanced forces c.) gravity d.) velocity