An investigation carried out to study the toxic effects of mercury was described in the article “Comparative Responses of the Action of Different Mercury Compounds on Barley” (International Journal of Environmental Studies [1983]: 323–327). Ten different concentrations of mercury (0, 1, 5, 10, 50, 100, 200, 300, 400, and 500 mg/L) were compared with respect to their effects on average dry weight (per 100 seven-day-old seedlings). The basic experiment was replicated four times for a total of 40 dryweight observations (four for each treatment level). The article reported an ANOVA F statistic value of 1.895. Using a significance level of .05, test the null hypothesis that the true mean dry weight is the same for all 10 concentration levels.