I have no clue u mean the game halo?
B- copper and zinc; I had to answer that question yesterday on my quiz
Cross sectional studies is the correct answer.
Cross-sectional research is used to examine participants' behaviors of different ages at one point in time. These studies are useful for a variety of reasons: data collection can be proceeded rapidly, the cost is a lot lower than a logitudinal research since there is no need to keep contact and follow-up with participants as time passes, and because of that practice effects are not a problem. On the other hand, the principal limitation of this research is that the results produce information regarding age-related change, instead of development per se.
<span>Prior to the standard gauge track, railroad travel was much more arduous and painstaking. There were originally several types of gauges used on a railway track. This caused long train trips to require multiple stops in order to change train cars. With the standard gauge track on trains in the 1800s, multiple changes were no longer necessary and so the trips were shorter.</span>
