Please help me answer all these questions, thank you.

[(1 There continues to be a lot of controversy regarding the use of Vitamin C both in the prevention of colds and other negative health outcomes. Recently, the Physicians Health Study II ms completed. In November 2008, a paper (Sesso et al., 2008) was published in the Journal of the American Medical Association which reported on some of the results of the Physicians Health Study II. Consider the following excerpt from the abstract of the paper: The Physicians' Health Study H was a randomized, double-blind, placebo-controlled trial of... vitamin C that began in 1997 and continued until its scheduled completion on August 31, 2007. There were 14,641 US male physicians enrolled, who were initially aged 50 years or older. 1 8. Explain what it means for the Physicians' Health Study II to be. . .. a. ...randomized. b. ...double-bljnd. c. ...placebo-controlled