Consider this quote from an article in the wall street journal: "the stock of educated workers isn't increasing fast enough to keep up with rising employers are paying the typical four-year college graduate [without graduate school] 75% more than they pay high-school grads. twenty-five years ago, they were paying 40% more. employers insist on ever better-educated, skilled workers. " source: david wessel, "lack of well-educated workers has lots of roots, no quick fix," wall street journal, april 19, 2007, page a2. which of the following best explains the rapid increase in the wage differential between college graduates and high school graduates?

he movement of air through earth's or any planet's atmosphere is called wind, and the main cause of earth's winds is uneven heating by the sun. this uneven heating causes changes of atmospheric pressure, and winds blow from regions with high pressure to those with low pressure.

i hope this : )

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.

the correct answer is: b. pantala flavescens, because these organisms would have a high level of genetic variation due to sexual reproduction.  

because involves two organisms (parents) whose genetic material combines, sexual reproduction leads to genetic variation in new generations of offspring. the offspring is an unique organism, with new genome, more protected with the higher ability to adapted. this process is fundamental to evolution.