Having more than 1000 students in a year, assume that I choose a simple random samples of 30 final exams in my engineering economics class and compute the class average. The results show that 5% of the grades are over 2.1 and 5% are under 1.9. Using this information, determine (i) the population mean and (ii) the population standard deviation of the final exam.    DO NOT USE EXCEL & PLEASE SHOW ALL CALCULATIONS AND STEPS.

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