Math Help - Mean and Standard Deviation of a random variable....

I know the answer for letters B,C, and D. I just need help with letter A, don't know how to interpret it.

A Statistician / psychologist can help you with your statistics in spss, amos, statistica, Econometrics, minitab, stata, r, gpower. I can do factorial analysis, correlation, time series, path analysis, anova, ancova, glm, non parametric (e.g. bootstrap), reliability, standardization, validity, mediation and moderation analyses can be done. Normality check as well plagiarism check is offered. We can also evaluate questionnaires. Private lessons are offered also using skype. estatistics. email: info@estatistics.eu.