Answer the following question given this paragraph: Electronegativities generally increase from left to right across a period. This is due to an increase in nuclear charge because of the greater number of protons in the nucleus. Alkali metals have the lowest electronegativities, while halogens have the highest. Because most noble gases do not form compounds, they are generally not assigned electronegativity values. Note that there is little variation among the transition metals. Electronegativities generally decrease from top to bottom within a group due to the larger atomic size. Q: Why do electronegativities decrease from top to bottom? Choices: - smaller atomic size - larger atomic variation - larger electric pull - larger atomic size A:
larger atomic size
Answer the following question given this paragraph: All living things depend on their environment to supply them with what they need, including food, water, and shelter. Their environment consists of physical factorssuch as soil, air, and temperatureand also of other organisms. An organism is an individual living thing. Many living things interact with other organisms in their environment. In fact, they may need other organisms in order to survive. This is known as interdependence . For example, living things that cannot make their own food must eat other organisms for food. Other interactions between living things include symbiosis and competition. Q: What is the term for when organisms need other organisms to survive? Choices: - intradependence - realization - coexistence - interdependence A:
interdependence
Q: Answer the following question given this paragraph: The immune system naturally becomes less effective as people get older. This is why older people are generally more susceptible to disease. Q: What system gets less effective with age, that generally makes older people more disease susceptible? Choices: - infectious system - reproductive system - nervous system - immune system A:
A: immune system
Question: Answer the following question given this paragraph: Figure 26.16 A compound microscope composed of two lenses, an objective and an eyepiece. The objective forms a case 1 image that is larger than the object. This first image is the object for the eyepiece. The eyepiece forms a case 2 final image that is further magnified. Q: What two lenses comprise a compound microscope? Choices: - polarized and focal - scope and focus - concave and convex - objective and eyepiece A:
Answer: objective and eyepiece
*Question*
Answer the following question given this paragraph: 25.7 Image Formation by Mirrors 53. What is the focal length of a makeup mirror that has a power of 1.50 D? 54. Some telephoto cameras use a mirror rather than a lens. What radius of curvature mirror is needed to replace a 800 mm focal length telephoto lens? 55. (a) Calculate the focal length of the mirror formed by the shiny back of a spoon that has a 3.00 cm radius of curvature. (b) What is its power in diopters? 56. Find the magnification of the heater element in Example 25.9. Note that its large magnitude helps spread out the reflected energy. What is the focal length of a makeup mirror that produces a magnification of 1.50 when a person's face is 12.0 cm away? Explicitly show how you follow the steps in the Problem-Solving Strategy for Mirrors. A shopper standing 3.00 m from a convex security mirror sees his image with a magnification of 0.250. (a) Where is his image? (b) What is the focal length of the mirror? (c) What is its radius of curvature? Explicitly show how you follow the steps in the Problem-Solving Strategy for Mirrors. An object 1.50 cm high is held 3.00 cm from a person's cornea, and its reflected image is measured to be 0.167 cm high. (a) What is the magnification? (b) Where is the image? (c) Find the radius of curvature of the convex mirror formed by the cornea. (Note that this technique is used by optometrists to measure the curvature of the cornea for contact lens fitting. The instrument used is called a keratometer, or curve measurer. ) 60. Ray tracing for a flat mirror shows that the image is located a distance behind the mirror equal to the distance of the object from the mirror. This is stated d i = d o , since this is a negative image distance (it is a virtual image). (a) What is the focal length of a flat mirror? (b) What is its power?. Q: What does a keratometer measure in the cornea? Choices: - diameter - Lenght - Width - curve A:
**Answer**
curve
(Q).
Answer the following question given this paragraph: Q: The total energy assimilated by an ecosystem in a give period is known as what? Choices: - size primary production - median primary production - mean primary production - gross primary production A:
(A).
gross primary production