Which of the numbers in this tree represents the most recent common ancestor of amphibians and lizards? a. 1 b. 2 c. 4 d. 3

The economist thomas malthus suggested that A people die faster than babies are born B there were soon be insufficient food for the growing human population C in the 1700s, England needed more housing D the majority of a species offspring die

How are tree rings used to date geologic events?

Why do tick bites itch when they are pulled?

If the sky is blue, why is water blue

In humans, cells that line the small intestine have hairlike projections that increase the surface area for the absorption of nutrients. What would happen if these projections were not functioning properly?

Which of the following is an advantage of nuclear energy over fossil fuels? A. Eliminates the need for mining. B. Uses a renewable energy source. C. Releases less CO2 waste products. D. Releases more CO2 waste products.

A cell with 46 chromosomes inside itsnucleus goes through one round of mitosis and cytokinesis. How manychromosomes are inside each of the two resulting nuclei?

The theory that explains how the earths surface is made up of moving rocky plates is called: A. Supercontinent B. Plate tectonics C. Sea floor spreading D. Continental drift

10. Which of the following is an emerging dis- ease that was unknown 50 years ago? a. malaria b. dengue fever C. Lyme disease d. schistosomiasis

What are the agents for deposition