Data was collected from 20 samples of adults between 1987 and 2008, a HES found that the average level of happiness reported by people less than 65 years old declined from 1987 to 1999. For this same group, the average level of happiness increased slightly from 2000 to 2008. In addition, the average level of happiness reported by people aged 65 and older increased from 1987 to 2008. (The) variable of interest in this study is (are)
a. age
b. age 65
c. 2008
d. 1987-2008

What is a self-improvement strategy for a parent with a busy schedule? a. spend more time watching exercise shows on tv. b. start exercising when the kids are grown. c. use a calendar to plan daily exercise. d. write in a journal about the importance of exercise.

As you sit in the library with your friend studying for your weekly quiz on the integumentary system, you come upon an article about the hazards of prolonged exposure to the sun's rays. your curious nature leads you to research the subject further. you're fascinated to learn that minimal exposure to the sun allows you skin to manufacture vitamin d, which is important to maintain homeostasis. you also read that although sunscreen can protect you from the ultraviolet (uv) rays of the sun, some medications can actually increase a person's sensitivity to the sunlight.

Which of the following best reflects what we know about how the flu virus moves between species? a) the flu virus in a pig is mutated and replicated in alternate arrangements so that humans who eat the pig products can be infected.b) a flu virus from a human epidemic or pandemic infects birds; the birds replicate the virus differently and then pass it back to humans.c) an influenza virus gains new sequences of dna from another virus, such as a herpesvirus; this enables it to be transmitted to a human host.d) an animal such as a pig is infected with more than one virus, genetic recombination occurs, the new virus mutates, the virus is passed to a new species such as a bird, and the virus mutates again and can now be transmitted to humans.