Using the Principal of Superposition, choose the statement below that is correct. A.) An archeologist digs into the Earth and makes a pile of the rocks and dirt he removes. The rocks on top of the pile are the youngest.
B.) A scientist studies a rock wall in the Grand Canyon. He is taking samples from half way down the wall. He knows that his rock sample is older than the rock at the top of the wall.
C.) A small shift in the Earth’s crust pushes a large piece of rock onto the surface. This rock is younger than the rock below it.

Which statements best describe the differences or similarities between a comparative investigation and an experimental investigation? check all that apply. experimental investigations are best for showing cause-and-effect relationships, while comparative investigations do not necessarily show this type of relationship. comparative investigations are often impractical and unrealistic, while experimental investigations are the most practical and realistic kinds of investigations. comparative investigations allow for the use of a wide range of variables but do not have a control group, while experimental investigations involve variables that can be controlled. both experimental investigations and comparative investigations are designed to answer scientific questions. both experimental investigations and comparative investigations focus on making observations rather than collecting new data.

In the ocean why are the greatest amount of primary producers found in the epipelagic zone and how does that affect biodiversity

Female luna moths (actias luna) attract males by emitting chemical signals that spread through the air. a male hundreds of meters away can detect these molecules and fly toward their source. the sensory organs responsible for this behavior are the comblike antennae visible in the photograph shown here. each filament of an antenna is equipped with thousands of receptor cells that detect the sex attractant. based on what you learned in this chapter, propose a hypothesis to account for the ability of the male moth to detect a specific molecule in the presence of many other molecules in the air. what predictions does your hypothesis make? design an experiment to test one of these predictions.