Given an Infinite Population with a Mean of 75 and a Standard

Given an infinite population with a mean of 75 and a standard deviation of 12, the probability that the mean of a sample of 36 observations, taken at random from this population, exceeds 78 is: $\begin{array}{|l|l|}\hline\text { A. } & 0.4332 . \\\hline \text { B. } & 0.0668 . \\\hline \text { C. } & 0.0987 . \\\hline \text { D. } & 0.9013 . \\\hline\end{array}$