Problem - a matter elevated for consideration or solution; "our research consisted of ten challenges to unravel" Longitudinal experiments entail observing and examining a case more than an extended period of time. This permits scientists to track alterations, developments, and trends that manifest after some time. raster font, screen font https://charliepfsig.bloguetechno.com/5-easy-facts-about-pay-someone-to-write-my-case-study-described-71562893