*Question*
Answer the following question given this paragraph: Population density just gives the average number of individuals per unit of area or volume. Often, individuals in a population are not spread out evenly. Instead, they may live in clumps or some other pattern (see Figure below ). The pattern may reflect characteristics of the species or its environment. Population distribution describes how the individuals are distributed, or spread throughout their habitat. Q: The average number of individuals per unit of area can be expressed as what? Choices: - the percent of population - percent density - total density - population density A:
**Answer**
population density

*Question*
Answer the following question given this paragraph: Electrons are one of three main types of particles that make up the atom. They are extremely small and have an electric charge of -1. All atoms have the same number of electrons as protons. Q: All atoms have equal numbers of what two particles? Choices: - nuclei and neutrons - photons and protons - electrons and neutrons - electrons and protons A:
**Answer**
electrons and protons

*Question*
Answer the following question given this paragraph: Electromagnetic waves generally propagate out from a source in all directions, sometimes forming a complex radiation pattern. A linear antenna like this one will not radiate parallel to its length, for example. The wave is shown in one direction from the antenna in Figure 24.7 to illustrate its basic characteristics. Instead of the AC generator, the antenna can also be driven by an AC circuit. In fact, charges radiate whenever they are accelerated. But while a current in a circuit needs a complete path, an antenna has a varying charge distribution forming a standing wave, driven by the AC. The dimensions of the antenna are critical for determining the frequency of the radiated electromagnetic waves. This is a resonant phenomenon and when we tune radios or TV, we vary electrical properties to achieve appropriate resonant conditions in the antenna. Q: A current in a circuit needs a complete what? Choices: - cause - speed - stream - path A:
**Answer**
path

*Question*
Answer the following question given this paragraph: Most amphibians breathe with gills as larvae and with lungs as adults. Additional oxygen is absorbed through the skin in most species. The skin is kept moist by mucus, which is secreted by mucous glands. In some species, mucous glands also produce toxins, which help protect the amphibians from predators. The golden frog shown in Figure below is an example of a toxic amphibian. Q: What do most amphibians breathe with as larvae? Choices: - pores - lungs - nasal passages - gills A:
**Answer**
gills