With age, muscles can become weaker. this is due to a. connections between nerves, which cause more pain and therefore less use. b. damage from everyday use and injuries that accumulate over time. c. disconnections between motor nerves and muscle fibers. d. difficulties that occur during muscle growth and repair.

Hi i need comment on my homework or something to add. *argue for and against quantitative and qualitative techniques respectively. which ones would you lean towards when conducting an investigation and why?   quantitative techniques, usually presented through surveys, are more practical, take less time, and can design samples in which any person or household of the target audience has the same probability of participating. however, the questionnaires must be carefully written by highly trained professionals, in such a way that they do not contain ambiguous or biased questions, that they are easily understandable by any member of the sample, and that they contemplate all the objectives of the research. besides that they do not allow to deepen in the reason of the facts. qualitative techniques, on the other hand, are based on the observation of natural behaviors, discourses, open responses for the subsequent interpretation of meanings. studying reality in its natural context can be extremely useful to learn more about the phenomenon studied. however, more specialization is required, they are not applicable to statistics, so it is not possible to make measurements, it entails a higher cost per studied population (which is also reduced), whose results do not necessarily represent the general population. i believe that knowing the situation of the general population, through statistics is essential. in addition, because of the possibility of studying a much larger population in less time and with less amount of economic resources, i would lean towards quantitative research.

Which two levels of the spine that can undergo flexion and extension?

*edit* i took the test and i picked a and it was incorrect for its c! rank the following suggestions for preventing std, in order of increasing effectiveness. 1) using latex condoms properly 2) using spermicidal foam or jelly with a monogamous partner 3) abstaining from sexual intercourse and genital contact a. 1, 2, 3c. 2, 1, 3