In a controlled experiment, how many variables are changed at a time

A scientist wants to study maing behaviour in crickets

What do hydrometers test A. the buoyancy of water B. the amount of oxygen in water C. the pH of water D. the pollutants in water

In complete sentences describe the atmosphere of early earth.

The white area at the base of the nail that is half moon shaped is the

An object in projectile motion will follow which path?

Which of the following groups contain organisms that have tissues and organ systems? A. prokaryotes. B. bacteria. C. eukaryotes. D. protists.

What colors can a turtle see

If rats are allowed to wander through a complicated maze, they will subsequently run the maze with few errors when a food reward is placed at the end. their drastic change in performance once given a reward describes

Favorable changes in species get passed down through the generations because of

The most common form of aggression seen in animal hospitals is