Acivil service exam yields scores with a mean of 81 and a standard deviation of 5.5. using chebyshev's theorem what can we say about the percentage of scores that are above 92? select one: a. at most 12.5% of the scores are above 92. b. at most 25% of the scores are above 92. c. at least 75% of the scores are above 92. d. at least 25% of the scores are above 92.